Found hitch pins that fit near perfectly.
The removable pins in the hinges were a PITA to get in and out, even using a hammer and driver; the hitch pins are a tiny bit narrower and go in and out without a struggle.
We did not use door hinges, no need. The three hinges we used are not supporting much of the weight of the fold down platform bed and occupant; the wall end of the platform rests on a board bolted to the cargo wall and the outside corners are supported via cam straps up through the roof pillars, so the platform is angle adjustable for a sloping site.