According to FamilySearch(IGI).
James HELEY, married Rachel LONON, 27 March 1831 @ Stewkley.
Rachel LONON is shown as born in County(Bucks) in the 1841 census
I would ask BucksFHS for a marriage look up(£1) from their database, which may give more detail, if you don't have access to the archives. I would also suggest a baptism look((£1) up for Rachel LONON.
Variants of surnames is not uncommon.
As he's is a commercial traveller in 1851 census, there is a death for Rachel HEALEY, o/n/d - 1851. Caistor, Lincolnshire. And another death in o/n/d 1847. Luton, Beds. The Luton one seems most likely.
Steve.
