What a lovely feeling, to have found him
Alison, it looks to me as if your family of Lampard/Lamport's didn't start off with that name. Much the same as my bunch, who started off as BRABY which later became BRAVERY as they moved from Sussex into Surrey. Finding this spelling variant might be a major break-through for you! I looked up other marriage's in the name of LAMPER on the SMI and the results are below, so that you can see the distribution of the name, which in turn might give you a clue as to where to look for your Henry Lamper's baptism,
16 Jun 1584 John LAMPER Katherine BISHOP Northiam, East Sussex
23 Aug 1608 Elizabeth LAMPER Robert IDEN Ewhurst, East Sussex
25 Jan 1613/4 Mary LAMPER William TRIM Northiam, East Sussex
13 Jun 1614 Margaret LAMPER Richard FRAUNCIS Northiam, East Sussex
25 Jan 1614/5 Mary LAMPER William TRIMME Northiam, East Sussex
13 Jan 1617/8 Joan LAMPER Francis EVENDEN Northiam, East Sussex
-- --- 1673 John LAMPER Jane COKERELL Archdeaconry of Chichester Marriage Licence
5 Jan 1673/4 John LAMPER Jane COCKERELL Binsted, West Sussex
23 Jun 1700 Mary LAMPER Nathaniel TALHERST Bodiam, East Sussex
27 Jun 1700 Henry LAMPER Ruth PAINE Brighton, East Sussex
27 Dec 1715 Sarah LAMPER Thomas MAYNARD Rye, East Sussex
7 Oct 1779 Ruth LAMPER Thomas SOUTEN Ferring, West Sussex
11 Oct 1792 Hannah LAMPER James HOCKHAM Steyning, West Sussex
15 Nov 1800 Henry LAMPER Mary SANFORD Steyning, West Sussex
11 Apr 1804 John LAMPER Elizabeth LISHER Sompting, West Sussex
29 Aug 1819 Hannah LAMPER Daniel FINCH Steyning, West Sussex
25 Aug 1822 George LAMPER Margaret WAATE Slaugham, West Sussex
12 Jul 1829 Jane LAMPER Benjamin CASE Steyning, West Sussex
22 May 1830 Harriet LAMPER David CAPLIN Sompting, West Sussex
8 Sep 1833 Ann LAMPER John BISHOP Steyning, West Sussex
9 Jun 1835 James LAMPER Sarah HOLLINGDALE Sompting, West Sussex
Jane