Hi T Moffat,
The Thomas first name is fairly unusual for McGeorges. There were a few in Urr around that date, but no Thomas born 1797. Unfortunately about this date there was a tax put onto parish register entries, so people of course didn't bother. I have quite a few McGeorges born about this date, but not in the old Parish Registers and had died before the 1851 census Very frustrating.
The closest Thomas I can come up with was born 1814, Urr, however he married Jane Blacklock 1850 in Urr. This family went to Missouri.
Who did your Thomas marry? Sometimes I can connect families through the wifes name.
cheers
Kay,Perth Australia