I'm so glad to hear that you've taken in Barney and that he's doing so well.

As for the heating pad suggestion, how about Snuggle Safe. I hope that you have a microwave because you just pop this in the microwave and heat it up and it's very safe for pets and people can also use them. Here's the link: http://www.snugglesafe.ca/index.htm. I think that some pet stores may carry these too.