It is for this exact reason I suggested a Canadian buy, sell, and trade section on FABO a few years back. By doing that it would allow the Canadians an opportunity to easily make transactions between one another, trying to reduce the insane international shipping and duties. For Canadians buying from US, the conversion together with shipping makes for a truly wallet lightening experience.
I have bought quite a few thing from south of the border. My rule of thumb, that usually works out pretty close for most things, is that if you double the asking price, that's what the ultimate cost is in CAD. for us to the door.