E-Waste Buyers in Canada???

As with anything, quantity matters. A couple hundred pounds of at least motherboard quality seems to be the entry point for small refinery set-ups in Canada to show interest in your material. The more you have, and the higher the quality, the more likely that you'll get closer to the prices you'd get out of US buyers. There may be a bit of confusion in the Canadian E-waste arena now that the ERPA is nation-wide. It may take a while for all of it to shake out to a stable market for buying/selling, and what it may mean for the flow of materials to your workshop.
You can read more here: EPRA - Electronic Products Recycling Association