Sounds to me like they tried to go live axle and use clamps. You need two, maybe three pillow block bearings, measure the axle diameter and make sure you get the right size, mount the pillow blocks in place of those clamps, and cut two tubes to evenly space the wheels that will fit over the axle without much slop, and mount those between the wheel and the pillow blocks, then align your sprocket and brake, based on what I see unless you go back to factory that is your best bet.