This is the transcribed will of Leonard Bucknor merchant of London, 1669 & 1671 (UK Public Record Office Catalogue Reference:PROB 11/337/623).

Leonard Bucknor was the son of Leonard Buckner (1593-1656), a prominent London apothecary, and Mary Richman (or Richmond) (cf. the will of Anthony Richmond Sr. of Idston, Berks, 1649).

I know relatively little of Leonard (Jr.), but he seems to have been involved in some skullduggery during the Civil Wars (as was his brother Thomas). Sotheby's recently auctioned a letter from Charles II dated 25 Mar 1657 requesting Leonard's release from custody after he had been arrested. The description notes:

This letter to the Governor of Dunkirk, then part of the Spanish Netherlands, dates from around the time of the Treaty of Paris, which allied Cromwell with Louis XIV against Spain. It seems likely that Leonard Buckner was a Royalist spy, perhaps using an assumed name. at Dunkirk engaged in some business for the King of Spain.

https://www.sothebys.com/en/buy/auction/2020/the-collection-of-a-connoisseur-history-in-manuscript/charles-ii-letter-signed-to-the-marquis-de-lede-25

If one examines the military gear in the inventory of Leonard's estate, this seems not unlikely, though it seems he was using his real name. It's not too much to think that Leonard was probably involved in the schemes of his notorious uncle Sir John Wildman, who allocated Leonard a princely sum in his 1671 will (likely never claimed as Leonard predeceased him by decades). He had also acted as Wildman's attorney in 1660 for a land transaction between the Bishop of Chichester (not, of course, his distant cousin John Buckner who was Bishop of Chichester over a century later) and Henry Bishop.

This is a sketch of the family relationships going back to Thomas Buckner, of Whitley, Berkshire, England (to the best of my knowledge as of this writing):

I've tried to preserve the line arrangement so anyone who wants can compare this to the original image. I don't claim perfection, and there are some things that can be interpreted different ways. The notation {ER} and such indicates a superscript abbreviation. These are common in period documents, though sometimes they can be a little idiosyncratic.

Date of will: 27 Oct 1669 in London

Date of codicil: 30 Sep 1671 in Dublin

Probate: 23 Dec 1671 in London

People named in the original will:

• brother William Bucknor (an apothecary who married Isabell Rountree, he seems to have inherited his father's guild freedom by patrimony)
• Theodosia Bucknor (probably orphan niece, dau. of brother Anthony and Barbara Roberts Bucknor)
• cousin Margaret Gardner (probably dau. of mother's sister Jane Richmond and Edward Gardner)
• cousin Mr. Edward Gardner (probably son of mother's sister Jane Richmond and Edward Gardner)
• cousin Francis Richmond (apparently a maternal cousin, probably son of one of mother's brothers, John or Anthony Richmond)
• Uncle and Aunt Wildman - apparently John Wildman and his wife Lucy. Some have claimed that Lucy was the sister of Lord Lovelace; however, Henry I. Richmond in Richmond Family Records (London: Adlard & Son, 1933) makes a very compelling argument that Wildman's second wife was Lucy Richmond, sister of Leonard Bucknor Sr.'s wife Mary Richmond, mother of the present Leonard Bucknor. John Wildman, Esq. was the executor of Leonard Sr.'s estate. Richmond's version would explain the term "uncle and aunt". Wildman, in his 1670 will, left the princely sum of 500 pounds to Leonard Bucknor and 100 pounds to his brother William Bucknor. Wildman - amazingly for a man of such risky pursuits - lived until 1693, so Leonard's legacy probably went unpaid, though the outcome of William's is unclear.
• friends Mr. William Parker and his wife (proprieters of the Nonsuch tavern on Bon Street in Covent Garden, a notorious gathering place for radicals - see for example R.L. Greaves, Deliver us from evil: the radical underground in Britain, 1660-1663, Oxford University Press US, 1986, p. 78 ff.)
• brother Thomas Bucknor (the most politically active member of the family, he seems to have been a pamphleteer for the Nonsuch plotters and was employed for a time at the London post office, also a notorious den of radicals and Wildman's cronies)
• witness John Perry (note that Leonard's cousin Thomas Bucknor of Youghal had a son named Perry Bucknor, christened in 1679, so this has a good chance of being a relative of John Perry Esq. of Youghal, ca. 1661-1712, also a wealthy Antigua planter)
• witness Thomas Feltham, scrivener
• Mr. John Billingsley, vintner of London - Billingsley seems to have been the sucker who bought Leonard's shares in the disastrous Canary Islands Company. I'm no lawyer, but I think the inclusion of this in the will is intended to make sure that the sale is iron clad. Leonard is probably trying to ensure that his estate does nothing to give Billingsley ammunition for a lawsuit. Not to besmirch the deceased, but I suspect Leonard knew he was selling Billingsley shares in a company that was on the verge of doing an Enron-style implosion.

People named in the codicil:

• cousin Thomas Bucknor, Esq., overseer (probably Capt. Thomas Bucknor of Dublin. I had previously thought he was Thomas Bucknor of Youghal, son of John Bucknor of Dromore, but now I think it's more likely that this is a son of John Buckner of Abingdon, Jr. There were many cousins named Thomas Buckner it seems...)
• children of overseer (cousin Thomas; at this time, his known living children were Ralph, Jane, Mary, and Elizabeth. This probably excludes Thomas of Youghal whose children were born in the late 1670s-early 1680s.)
• unnamed cousin Buckner in Oxmantown, Ireland - it seems likely to me that this was Thomas Buckner or "Buckener", a glazier who lived around this time in the parish of St. Michan in Oxmantown, which was undergoing a rapid urban development program organized by the Corporation of Dublin. I would tentatively propose that he was a cousin of Leonard Jr. via a son of Phillip Buckner, Leonard Sr.'s eldest brother.
• cousin William Buckner, clerk (one of the many sons of John Bucknor of Dromore, Waterford; William died testate around 1700 and was later a member of the Irish parliament for Waterford)
• Mr. Harris
• Mr. Thomas Tyther (relationship smudged) and wife
• servant Henry
• William Parker (as above, explicitly identified with the Nonsuch tavern in the codicil)

In the name of God Amen
this seven and twentieth day of october Anno Domini 1669 And in 
the one and twentieth yeare of the Reigne of our Soverayne Lord Charles
the Second by the grace of God King of England Scotland France
and Ireland defender of the ffaith/I Leonard Bucknor of London
merchant being in good health of body and of sound and perfect mind and
memory (Prayse be therefore given to Almighty God) But being bound 
out upon a voyage beyond the seas And Considering the Dangres thereof
And the ffrailty of this transitory life and the Certainty of Death Doe
therefore make and declare this my last will and Testament in manner
and forme ffollowing (that is to say) Ffirst and before all Earthly
things I recommend my sould into the hands of Almighty God. As unto the
hand of a ffaithfull Creato{R} And my body I remitt to the Earth whereof it 
was fframed in assured hopes of a Joyfull REsurrection And touching such
Temporall Estate as it hath pleased God to bless me withall in this life I
dispose thereof as followeth First my will and desire is that all such debts
as I shall justly owe to any person or persons att my decease shall be satisfyed
and paid with all convenient speed after my decease Item I give 
and bequeath unto my brother William Bucknor the sume of Fifty pounds in money Item
to Theodosia Bucknor the sume of Twenty pounds in money Item I give
and Devise unto my Cosen Margarett Gardner the sume of one hundred
pounds in money Item I give to my cozen Mr Edward Gardner the sume

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Of thirty pounds in money Item I give and dispose to me Cosen Francis
Richmond the like sume of Thirty pounds in money Item I give and bequeath
unto my uncle and Aunte Wildman the sume of Forty pounds (this is
to say ) to each of them Twenty pounds to buy them mourning Item I doe
give and bequeath unto my good Friends Mr. William Parker and his wife
living in Bon Street in Covent Garden the sume of Twenty pounds (That
is to say Ten pounds each to buy them mourning And all and every the
Rest residue and Remainder of my Estate whatsoever not before herein
bequeathed and disposed of my debts being satisfied and paid and my
Funerall Charges defrayed I give devise and bequeath unto my Bro
ther Thomas Bucknor And I doe hereby make nominate and appoint
my said brother Thomas the sole and onely Executo{R} of this my last
will and testament Revoaking and hereby repealing all former and 
other wills by me made Provided alwayes neverthelesse And my 
true intent will and meaning is that all and every my Stocke and
Adventure which I subscribed and paid into the hands of the Company 
of Merchants Trading to the Canaries Comonly called the Canary
Company shall not be deemed or accompted any part of my Estate For
as much as that for valluable Consideracons I have transferred and
made over the same to Mr. John Billingsley vintner of London And I
doe strictly Charge my said Executo{r} after my decease Doe make and give
unto the said John Billingsley his Executo{R} or Administrato{R} such power
and Authority And doe such Acte and Acts for the Better recovery of
the said Adventure by the said John Billingsley to his and their owne use  
and uses ashe or they shall reasonably require In witnes whereof
I have hereunto put my hand and seale dated the day and yeare First
above written/ Leo: Bucknor / Signed Sealed Published and declared
by the Testator as and for his last will and Testament the day and
yeare First above written in the presence of John Perry Tho:
Feltham Snr

Memorandum that I Leonard Bucknor of London Merchant
bee[?] att present resideing in the Citty of Dublin in the Kingdome of
Ireland having made my will in London and left in the hands of my
trusty and loving Friend Mr William Parker living att the signe of
the Nonsuch in Bon Streete in Covent Garden and being att present sick
and weake of body but of sound and perfect memory (Praised be Almighty
God for the same) Doe declare and pronounce And it is my desire that
my said will Remaining in the Custody of the said Mr Parker do ----
stand remaine and be as? my last will and testament onely with this
my Additionall declaration to be annexed to my said will (that is to say)
Imprimis now as formerly I bequeath my soule into the hands of God
my master firmly hoping --- and believing through the meritorious
death and passion of Jesus Christ my blessed Saviour and Redeemer to re[?]
to me Free pardon Admission and forgiveness of all my sinnes And as for
my body to be buried in Christian buriall Att the will and discretion of my
overseer hereafter nominated Item I give and bequeath unto my beloved
Cosen Thomas Buckner Esquire The sume of Five pounds and a Ring (whom
I design and declare to be overseer as well of my said Former will and of this
my Additionall declaration or to appoint whom he shall thuch[?] sett in his
Steade /Item that all my Just and due debts which may accrue or
arise by my Funerall Charges or otherwise may be paid and discharged

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By my said overseer or who he shall appoint Item I give to each of 
the children of my said overseer a Ring And alsoe to my Cosen Buckner
in Oxmantowne [Ireland] another Ring And to William Buckner my Cosen Clerke -
to Mr Harris a Ring And [smudged] to Mr Thomas Tyther and his wife
each of them a Ring And to my servant Henry Forty shillings in money
besides his wages due unto him with such of my Apparell and Clothes
as my said overseer shall thinke fitt and meete for him And lastly I
do hereby declare desire and pronounce that my said will and testmt.
remaining in the hands of the said Mr. Parker shall not in the least be
Anulled anihilated or made void by these presents or anything therein
Conteyned. In Witnes whereof/ I have hereunto sett my hand and seal
the thirtieth day of September 1671 Leo: Buckner./in the presence
of William Buckner/

Probatum fuittestamentum suprascriptum unatum codicillo
eidem annexo apud aedes Exon scituat in Le Strand in Com. Midd. coram venbli.
viro domino Leoline[?] Jenkins milite legum Dctore Curia Prerogativa Canto.
magistro custode sive commissario tibinse[?] Constituto vicesimo tertio die mensis
Decembris Anno Domini Millesimo Sexacentesimo Septuagesimo Primo 
Juramento Thoma Bucknor Extore. in huius modi testamento nominato
Cui commissa fuit Administrato omnium et singulorum bonorum Jurium et
Creditorum dicto defuncto de bene et fideliter Administrand. eadm. ad sancta
Dei Evangelia jurato.