I recently went the other way (US to Canada), and it was a pretty painless exercise -- other than having to pay the HST
. I would expect the process to be equally easy going the other way, but here's a link that might get you started
One thing to note, if the boat was not made in the NAFTA zone (Canada, US or Mexico) then you may be on the hook for import duties. Coming to Canada that would have been an extra 9.5% for us.