Old dump wagons

We are looking for some old 1920s to 1930s four wheel bottom or end dump wagons to pull with old gas 20s and 30s and larger antique Caterpillars. We want to haul dirt loading from the Cat 60 elevating grader that is getting restored and will be pulled either by a RD7 or by a Diesel 75. We are trying to make an original as possible working road building site to run at the yearly Memorial Day Weekend show at Santa Margarita. We will entertain any size, shape, or even pieces. I appreciate any responses here or by PM if you have anything, or have seen any setting about.
Thank you,
Roger

Old dump wagons