There is a company called Austin Works East, 25 Tarragon Drive, Sandwich MA 02563 Phone 001 (508) 833 3109
I have no idea what the scale of their business is, but at least they are in the same country, worth a call.
There are a number of Austin enthusiasts in Canada, especially BC. Try Roy Wilkins, email@example.com
I'll let others give you an idea of what they have spent recently on rebuilds.