If you didn't run the lights, it's only 33kW motor, less in newer Starships

Assuming you had 208V 3ph, that's under 100A. Much less if you are in commercial area with 240V 3ph

If you don't plan to spin 48 people, you could replace motor with a 120V single phase motor 5hp and remove a lot of weight from the ride (cut holes in every other fiberglass panel)

A decently small generator (relative to a full trailer carnival ride)... could power this. There are many tow behind 50kVA diesel generators. (Another $8k)

BTW the reason these UFO/gravs are for sale is because they are all rotting, the fiberglass panels that hold it together are like paper now and too expensive to repair.