There was a dealership by Buffalo. Forget the name. Anyway, their stance is they cannot sell to Canandians NEW cars, only used. However (and they implicitly stated "read between the lines"), per them, Toyota, nor the dealership, actually check on the US address given to them. So now you just have to find a dealership willing to co-operate.
But like the above, you're buying a RAV4. I think these are still built in Japan, are they not? Then you're subject to ~6% duty on top of GST. Have you factored those costs in? Also, flying down there/driving down, eating, hotel costs... Those don't come cheap. For $2,000, it is almost enough to persuade me just to buy Canadian (to have km, Canadian spec, etc...). Anything more (like say $3k and up) then I'd go to US. My dad's Van, he saved about $10k (was brand new). My Subaru, I probably saved about $5-6K, but ONLY if I bought from a dealership used. If I bought from a private sale here, my savings would probably only be about $2-3k at most, but my issue was that I couldn't find my car in the specs I wanted.
If you're buying used, I'd just buy from private sale locally to avoid GST, and you'll probably come out to something close to what you'd be paying for a used RAV4 from a US dealer.
My 2 cents.