Take notice, there are 4 small bearings, 2 on each side where the axle rests.
I have one similar to that somewhere in my garage, I think. It might have went bye bye in my garage fire a few years back.
I know the bottom had 4 pieces of angle iron welded together in a square with some feet to keep it from falling over.
Had 2 pieces of flat steel welded onto the square with gussets so it couldn't collapse. Whoops, forgot I 'C' clamped the sides together and drilled the 4 holes for the bearings. Then welded them to the base.
Added the bearings and you were good to go.
