You'll need to call them. Some of the names listed on Pioneer's web-site do not ship any product to Canada. I had looked at the same thing a year ago. Some tell you right on their web-site, while others you'll have to call.
If you don't care about a mfgs warranty or your fine with a retailers warranty then you should check out
www.borderfree.com. There is a listing of US merchants that have signed up to sell across the border in Cdn$ and their prices include freight & duty.
I've purchased cords, surge protectors and such from some of them. Saved about 50%. I don't have the guts to do it with anything as expensive as a receiver. That said... if its more than 50% savings... you can buy two.