Not sure about the shipping charge bro, but customs will only charge you the GST and PST on the declared value of the order as displayed on the shipping slip. Depending on the shipping method, the courier will also charge you a brokerage fee, FedEx and UPS are very expensive ($30.00 and up) postal service I think is a flat rate of $5.00. You can however clear the package through customs yourself and save the brokerage fee. All you need to do is phone FedEx with your tracking number and have them hold it for you at the local depot, then you need to take the paperwork to a customs canada office and pay the taxes there. Bring the stamped paperwork back to FedEx and then they will release the package to you. I order a lot of automotive parts (and some supplements) from the US and I've done this dozens of times.
Hope that helps!
Hint: If the declared value is $20.00 or less they do not collect the taxes.