I usually ship Canada Post. CP is cheaper on the insurance, about 1.00 per 100.00 and purolator is like 3.50 per 100.00. Shipping cost all depends on the size and weight. You can get estimates from their websites.
Oh but Canada Post does NOT provide signature but Purolator does and also picks up from your door but you do need to do some paper works for customs.
I also use Canada Post. If you're close to a postal outlet just get it weighed and measured there. Then the online calculator should work perfectly. Also if you go to the outlet you'll know if how much your packing materials will cost and whether you want to include their price in your shipping costs.