for transporting the sliding door;

find someone driving down to one of the upcoming Syncro events in a
compatible van, swap the sliding door before they leave...put their original
slider in their garage.

Drive van down to Cali, swap door with one of Bens spares (a crappy one) for
the trip home.

Swap again when home in Canada.

Sounds like a lot of work but only 10-15 minutes to replace each sliding
door.