Kyle, this may be a dumb question, but is there any way you can build your own sled? I designed and built a sled for my video equipment and it will easily hold a full grown man, chair, and video equipment. You could jump on it no problem.
The casters are a series of roller blade wheels angled in pairs at 45 degrees mounted to a piece of angled metal on each side. The rails are PVC which is pretty cheap to add as much length as you need. I used doweling inside the PVC for quick assembly/disassembly (you can’t use normal PVC couplings because the outside must be smooth for the wheels).
The only problem is, I’m not sure where your feet need to land, and the PVC rails may be in the way, in which case you would have to trench a little. Or, maybe just forget the rails and build a sled for a wide open space like a parking lot and add a simple brake. Anyway, just a thought. It would be great if you had an opportunity to practice on something close to the real deal before the combine.
“I’m a good driver.” – Raymond Babbitt in “Rain Man”