Hi Cheryl, The AVRI set of 4 CDs is only known by that name; and can not be sold in Australia. A friend in US bought me the set for about AU$10 from memory, a few years ago. The Church of Jesus Christ Latter Day Saints (LDS) put it out, and I think you can look at them at their Family History Centres throughout Australia.
The list of centres is on their Familysearch website, but I know many Rootschatters have the AVRI, so can help with future lookups, if needed.
I had a look in my local library yesterday for Gambrill, but only came up with Geo. Gamble again. On the 'Digger' Tassie CDs, he was there again, but buried on the 24 Nov 1837, Reg HOB(art).
So glad you found your man.
Regards Irene