I saw this BBC article where there are a lot of 3 legged dogs needing homes
http://news.bbc.co.uk/1/hi/scotland/glasgow_and_west/6513259.stmOtherwise, I found this list - maybe there are some she hasn't tried yet.
Dog Aid Society of Scotland:
0131-668-1063
Dogs Trust (was NCDL) HQ 0207-837-0006,
West Calder: 01506-873459.
Dumfries & Galloway Canine Rescue: 01387-770210.
Argyll Animal Aid: 01631-710245.
2nd Chance (Old dogs & pups- Fife) 01592-771933
Home A Dog Association & Golden Oldies(older dogs)Bandeath (Stirling): 01786-812908
Edinburgh Dog & Cat Home: 0131-669-5331.
Mrs. Murray's Stray Dog & Cat Home (Aberdeen): 01224-483624.
DAWGS 01224-208989
BAARK (Banff): 01888-563248.
Dog Rescue Service (Glasgow) 0141-556-3609 07833-970118