Digging around other possible places for British ironworkers and their families to turn up in France, and found a few places in Eure, closeish to Le Havre. One is Pont Audemer, home to Les Forges de la Risle:
http://www.gracesguide.co.uk/Forges_de_la_RisleRecords can be found here:
http://archives.eure.frIn Pont-Audemer are births:
Thomas Perry, 31 Jan 1837
- not yours, the child of William Perry and Mary Anne Mawdsley
deaths:
stillborn child Perry, 27 Dec 1846 - the child of John Perry, aged 25, and Mary Ann Ward, aged 26, his wife
Rebecca Perry, 28 Dec 1846 - aged five, the daughter of Richard Perry, puddler (English), and the late Rebecca Perry.
Perhaps William and John were part of a wider family network and link into Richard and Rebecca somehow? At any rate, this does show us that Richard's wife Rebecca was deceased by 1846, even if we can't locate the birth of Thomas...