ts sill in the planning stages but I have found vendors for every part including the hardware for a wagon seat.
These are top grade new parts, ready to paint. The wheels have modern hubs that run on ball bearings with rubber tires. They are sanded and can be stained are painted. The complete gear can be assembled in a weekend by a couple of handy guys or gals with a few hand tools and maybe a six pack or two.
The body hangers will have to be heated and bent and the reaches an reach braces will need to be heated and fitted from 3/16 x 1" flat bar stock that you furnish but is readily available from any local welding shop.
I have built and driven almost every style of light wagon and buggy that you can image. My favorite for versatility and durability are a spring wagon with a 9' bed and a buck board that is 9' overall.
These vehicles have no upholstery to deal with and I built them out or quality hardwood. Both vehicles had the metal parts painted black and the wood work has a cherry stain, finished with a high gloss marine varnish on metal and wood. This kit with a few modification could be used for the gear for ether one. Shaft and pole kits will be available.
Some of these parts like the wheels will have to be shipped by truck freight and you will need a commercial address for shipping.