At one time, Camping World had luggage like generator bags with an extendable handle, wheels and pockets for generator accessories. They had a cardboard bottom that probably was the reason for dropping the product. I added plywood and better feet to my bags and they work nice now, I can simply roll them to the tailgate and then grab the strap to lower them to the ground. Maybe something like that is available from another source.
Weatherstripping is available to help with the dust problem in a capped pickup bed. It is not perfect, but helps a lot.