Family history

I have been researching my Scottish ancestry for a number of years now, and have been very sucessful so far.  The only stumbling block is trying to find the grave of my ggg grandmother who died in Ayr during childbirth in 1822 age 19.  I have tried various genealogy societies in Scotland, and enquired through libraries in Perth and Ayr, cemeteries etc. to no avail.  I was told that she was buried in Alloway Old Kirk cemetery, but have not been able to have that confirmed.  My enquiries have been online as I am in Australia.  Can anyone give me any clues where I could try next.

Many thanks

Pauline Campbell