Your ancestor's name may not be Abraham George but rather Abel George. I have a note from the Family Search Online list, which admittedly is not 100% correct, that someone called Abel George came from Knocknashane, Armagh, Ireland. He was born about 1760 and was the son of William and Hannah Cunningham. There was a very close connection at that time between Northern Ireland and Scotland, and Cunningham is a Scottish name. Have you tried ORIGINS, which is the online site for Scottish birth, marriage and death records?