If you have paperwork to show the part emanated from the US originally then the importation process will likely be easier.
We re-imported 2 cars a month ago and the carrier asked if I worked for the FBI or US government as it was the fastest crossing he'd had. We had all the original US export paperwork (admittedly it had only been 12 months) but it sure made for a a breeze on importation. And yes we are back in the USA, actively looking for my next challenge in life!
A note on shipping parts from the US to Canada for my Canadian friends, if at any time there are parts etc. that you require that a vendor/seller will not ship USPS, then ship it to me in Reno, NV and I will happily combine shipments if required and forward. This may incur a small penalty for shipping twice, but likely better than the UPS cross border fees.