William Seaman born in Norwich

[kiterunner]

My 3xg-grandfather William Seaman, whose army papers I found on Findmypast this morning, joined the army at London 31st Mar 1834 giving his age as 20. He gave his age as 34 on his second marriage 19th Nov 1847, and his father's name as William Seaman. He died 22 Jul 1901 and his age is given as 83 on his burial record. So he was born about 1813 - 1818, and I would think it's more likely his age on the burial is wrong than the age when he joined the army, which would mean probably born nearer to 1813 than 1818. His army papers say he was born in the parish of St Giles, Norwich, Norfolk, so why can't I find a likely baptism for him? Help, please!

I should add he was in India nearly all the time he was in the army, and after he was discharged, so there are no censuses or GRO certificates to help. But I did think once I had a birthplace for him I might get somewhere! I might have known it wouldn't be so simple!