If you simply must get 315's to Canada, I recommend sending them via a new private courier service. It's called Eugenio_SSpress. The Eugenio_SSpress service will dispatch a very fast Camaro to your location to pick up the tires in person and hand deliver them to Montreal in record time. Shipping isn't cheap, and there isn't much room for anything else (two sets of tires at once is completely out of the question). But, they do great work.
Since this thread is worthless without pictures, here they are:
And yes, the top did still go up.