HI Gary,
I live in Quebec and order mostly all my kits from the US. Prices are way too high here, and the postal cost is not that much higher. You probably order from J. Coulombes (he is a great guy and i go there when i need something rush) . No duty, only PST and GST as you would pay if you buy in Canada. And since the exchage rate is pretty low, savings are even greater.
I order my PSI from Pens of Color and Woodtuningz (both great reseller).
Berea kits can be order directly from Berea (read their crafter program, it's really nice, you can order 10 kits of 5 models and have the 50 quantity price discount on everything) or with Ernie at Beartoohwood, again great reseller.
CSUSA kits are ordered directly forn them. Great people to deal with also.
You will fing their link on the home page of IAP.
If you absolutly want to order from Canadian sources, there are Lee Valley that sells Berea kits at 2 to 3 times the cost and Woodchucker. Google them and you will find their site.
They might be some other but i never tried them
I've been ordering from the states for almost two year, totalling about 20 order and never had any problem with mail or custom. Even sometimes, parcel just go thru the custom and you don't have to pay for PST and GST.
Hope this help you
Alfred