Or you could go with a precious metal dealer that's already in Canada... and you don't have to worry about import fees and duties.
Usually items that cross the border and have a declaired value can be subject to custom fees as there's paperwork to fill out.
Usually the fee is the same.. not a percentage of declared value... So regardless if the item is $2000 or $200 the fee may still be same.. they have to pay someone to do the paper work ...
I recommend looking at some place north of the 49... they deal in CAD so your card doesn't ding you in exchange fees ... there's no problems dealing with it going across the border.. it's a much better shopping experience IMO.
If you're that set on ordering stuff from the states I would suggest that you have a P.O. box or place where you can ship to in the states pick it up and bring it back yourself...