Looking at the Sussex Marriage Index (SMI) this is the best one between a George & Mary. As you can see Mary is 17 which gives a DOB of about 1819. The DOB Ricky found on 1851 was 1816 & that Mary appears OLDER than her husband, so some debate there
The other marriages on the SMI between a George Ayling & a Mary are earlier;
2/4/1821 to Mary Ann VERALL, Boxgrove, W. Ssx
12/8/1826 to Mary Goodyer, Yapton, W. Ssx
17/5/1829 to Mary HAYLER, Slaugham, W. Ssx
So this looks the best bet & certainly looks like the same couple Ricky found in 1851.
Archdeaconry of Chichester Marriage Licence, 2 Apr 1836:
George Cater AYLING, bach S.Andrew Chich.
Mary FOGDEN, sp 17 wcof Thos.yeo
wcof=With Consent of father, Thomas, yeoman. The marriage took place 3 days later.
Boxgrove, West Sussex, 5 Apr 1836:
George Cater AYLING, S.Andrew
Mary FOGDEN, (lic)
This looks to be the same couple in 1841 that Ricky found in 1851;
1841 - Boxgrove HO107/1100/3/15/4
George Ayling 20
Mary 20
William 6mall born Ssx.
No name on the SMI, IRACIS.
Di, I think it might be a good idea to find William's death/burial in Oz, then his marriage details, then his passage from the UK. I think his death certificate might reveal how many years he was in Oz which would narrow down your search.
The Sussex Family History Group has a parish map that you can print out which will help you see where you are
http://www.sfhg.org.uk/newmap_of_parishes.htmljane
