Hi!
I think this thread addresses the higher prices for on-line purchases at SU!
Forums at Splitcoaststampers
I don't believe that the differences that you saw were Canadian prices, but the cost if you purchase directly through SU! The least expensive method is to purchase through your SU! demo's website. If your demo does not have a website you can order through SU! and list your demo for reduced pricing (but not reduced shipping.)
I am not a SU! demo, so if I am incorrect, I am sure that one of the fine SU! demos on this board will correct me.
HTH
Kristina