Hi, It's some time since I looked up the info and I'm fairly certain most of it came from LDS records. I've, in the past, used the parish records as published on the net at:-
<http://www.knightroots.co.uk/transcriptions/Parishes_P/Portsea_Portsmouth_
Southsea>
Hope this is of some use, regards, John.
Addenum, I did find one other ref., to W H Leaf born 31st Jan 1793 Portsea
baptised at St Marys, Portsea on 20th Dec 1807. Father John and Mother Mary.