DIY spinner.

The cost of making it is negligible with an empty cake box and a piece of wire.

The wire is bent into a shelf like this

Prick a small eye in the center of the cake box, and then make a hole that the hamster can get into.

Insert the cake box on the stand and it's done.

Note: The wire is equivalent to a horizontal bar for hamsters, and it also has the function of grinding teeth.