Taken from BucksFHS - St Mary the Virgin, Amersham Parish registers Transcripts CD.Marriage - 23 Sep 1833. by Banns.
Joseph(x)WALKER, Bachelor.
Mary(x)WINTER, Spinster of Penn.
Witnesses - James Turner & Lydia(x)Winter.
Banns - 25 May 1845, @
Holy Trinity, Penn.
Joseph WALKER, Widower of Amersham
Rachel GRIFFIN, Spinster otp
Marriage - 9 Jun 1845. by Banns
Joseph(x)WALKER, aged FA, Widower of Coleshill, parish of Amersham, Labourer son of Richard Walker, Labourer.
Rachel GRIFFIN, aged FA, Spinster of parish of Penn, Bucks. Daughter of George Griffin, Sawyer.
Witnesses - Richard(x)Walker, Rebecca(x)Griffin & Geo Priest.
Burial - 30 Oct 1844.
Mary WALKER, aged 33 of Stock Place, Coleshill, Amersham.
Burial - 28 Aug 1864.
Rachel WALKER, aged 52 of Coleshill, Amersham.
No baptism in Penn, BUCKS, Wendover, BUCKS, PR's, nor Amersham, BUCKS, PR's, for Joseph Walker, 1800 - 1820.
Census returns give p.o.b for Joseph Walker as Wendover(1861), Amersham(1871) & Wycombe(1851). I would tend to ignore the 1841 census for p.o.b as Hertfordshire, but maybe worth checking if a result can't be found in Bucks.
I would suggest a burial and a baptism search from BuckFHS. £1 for each individual burial and baptism search.
There are baptisms for his children in Amersham PR's, with both spouses, ie. Mary Winter & Rachel Griffin.
Firstly, which maybe of interest.
Baptism - 6 Jul 1825. Richard, son of Richard & Jane WALKER, of Winchmore Hill, Amersham, Labourer, private baptism. (Seems to appear in 1841 census with Joseph).
Marriage - 16 May 1819. by Banns
Richard(x)WALKER otp
Jane BURROWS otp
Witnesses - John(x)Younge & J Priest. _________________________________________
Baptism - 8 Jun 1834. Lucy, child of Joseph & Mary WALKER of Amersham, Labourer.
Baptism - 20 Aug 1837.James, son of Joseph & Mary WALKER of Whinchmore Hill, Coleshill, Labourer.
Baptism - 22 Sep 1839. William, son of Joseph & Mary WALKER of Winchmore Hill, Amersham, Labourer.
Baptism - 6 Dec 1846. Mary, daughter of Joseph & Rachel WALKER of Coleshill, Amersham, Labourer.
Baptism - 8 Jul 1849.Elizabeth, daughter of Joseph & Rachel WALKER of Coleshill, Amersham, Labourer.
Baptism - 25 Jan 1852. Alfred, son of Joseph & Rachel WALKER of Coleshill, Amersham, Labourer
Baptism - 29 Jul 1855. Emily' daughter of Joseph & Rachel WALKER of Coleshill, Amersham, Labourer.
From BucksFHS - Holy Trinity, PENN Pr's CD.Baptism - 11 Jul 1813. Rachel, daughter of George & Rachel GRIFFIN
** of Penn, Labourer.
Marriage - 29 Jun 1812 by Banns
George(x)GRIFFIN, Bachelor otp
Charlotte(x)SLATER, Spinster otp
Witnesses - Richard(x)Bovingdon & Elizabeth(x)Carter.
I think the mother as Rachel Griffin
** is a mistake, as all other baptisms to George Griffin are with Charlotte.
___________________________________________________________________________
Baptism - 29 Sep 1811.
Mary, daughter of James & Mary WINTER.
Baptism - 7 May 1815. Lydia daughter of James & Mary WINTER of Penn, Labourer.
(Witness at Mary Winter marriage.?).Marriage - 22 Oct 1808 by Banns
James(x)WINTER, Bachelor otp
Mary(x)ROGGERS, Spinster otp
Witnesses - Jothan(x)Winter & Hanah(x)Brook & John Darvill.
Hope this helps a wee bit.
Steve.