I know this thread is a year old but since it's been brought back up, I'll add my thoughts.
If you're looking at a comparable option to American Frames or Dick Blick or Pictureframes.com or others then you'll be looking for a long time. There isn't anything. Canadian sources simply can't order in the volume required to be able to offer those kinds of lower prices. It's the same with printing. I can order a print from a U.S. printing house and when shipping and taxes are included it's still significantly less expensive than a comparable quality shop here in Canada.
If price is a big driver of choosing a supplier (and it is for many), get used to ordering from the U.S.
One option is to print as much as you can in stock sizes. This will allow you to buy ready made frames and you can pick up some from time to time when some retailers have them on sale. It's not ideal, but it does work.