Despite the fact that we are Marathon deck dealers, due to the size of your truck bed we would strongly suggest to you for the safety of all, yourself and other motorists, to consider getting a small trailer to haul your sleds around rather than a deck. You may be able to find either a two place open or a single open trailer to meet your needs.
If ou are looking at payload ratings in the sales brochure or similar thery are BS, not even close to what your truck can actually haul. You have to scale the vehicle. The weights in the brochures are for a stripped down base model usually. The chevy half ton I looked at a while back could only haul 500 lbs, the brochure was something like 1600 lbs.
This one is for sale in kelowna looks like it might work.