H-F still sells the folding trailer & several others.
A year & a half after hauling the XS 650 to Tennesse we moved back to Port Aransas. On the trip back I hauled a Norton Commando using a carrier made from an RV rear bumper made of square tubing that originally stored the sewer hose. Mounted it to the trailer hitch & cut 'slots' in the top for the tires to fit in. Found out quickly it wasn't very stable until I added turnbuckles at each end that hooked into holes drilled in the bumper. I had a '64 GMC panel truck at the time, & built a matching trailer from a wrecked '62 Chevy panel. Total cost = $0 because I sold the front half (engine, trans, doors, etc.) to a salvage yard. For the trip back I mounted the carrier on the trailers bumper & put our refrigerator on the tongue to balance the load. Worked perfectly & gave us a place to store things after we found a house to live in.
All that because I thought the price U-Haul wanted to rent a trailer for the trip was ridiculous. Also didn't have to rent a storage unit the day we got here so we could turn the trailer in.