Nikki,
I think I can supply the marriage you are looking for, although the bride's name is SAWE, not LAW
SAW without an 'E' is a name that occurs regularly in Tring - I'm not aware of having seen LAW much. I suspect although spelt 'SAWE' below, it was more usually 'SAW'.
Anyway the marriage is as follows....
St Michael & All Angels, Aston Clinton, Bucks
18th September 1826
James CHAPMAN (X), Widower OTP
Charlotte SAWE (X), Spinster OTP
by banns
Witnesses
John KIPPING
George HARROWELL (X)
James, Charlotte, and children George & Sarah Ann, who appear at Hale Wood, Wendover in the 1851 census, are just 2 addresses before my great great grandparents Thomas and Sarah PENN, (plus Sarah's mother Maria PALMER) at Miles Field, Wendover.
It never amazes me how often these coincidences come up.
These 1851 addresses, whilst technically in Wendover parish, actually lie geographically closer to St Leonards, which was part of Aston Clinton. This may explain why the marriage took place in Aston Clinton, rather than Wendover.
St Leonards church was not permitted to perform marriages at this date, being one of those "closed down for business by Hardwickes Marriage Act 1754. There were no weddings there again until, (I think, from memory), 1861.