I bought a set of Rack Time panniers (I think the model is called Travel-It) from Sierra Trading Post for under $50.00. They are made by Ortlieb, and have the Ortlieb attachment system. They seem to be sturdy and well made and have built in rain covers which I haven't used yet. When you join Sierra Trading Post they give you an additional discount for joining. Considering the costs, the price plus shipping to Canada may still end up cheaper than most things you'll find elsewhere.
I just ordered these Racktime rear panniers as well from Sierra Trading Post. I got them for under $50 as well, and total came to $53+ with shipping for the pair. I like the fact that they have the built in rain covers also, and it looks like just enough additional pockets for misc items. I'm really looking forward to trying them out.
PSA - check out the website for retailmenot.com and enter in Sierra Trading Post. There was a 20% and 30% off item coupon there last time I checked. Not sure if they are still valid, but worth a shot.