This is a simple version of the ubiquitous spinning toy. Only need a ball bearing, better if it is ceramic.
I bought this:
https://www.aliexpress.com/item/1pc-Hand-Spinner-bearing-Si3N4-black-ceramic-BSB-Speed-Swiss-Bearing-608z-Skateboard-scooter-wheel-Freeline/32628486005.html

The balls I use are from a old big broken ball bearing that I dissamble. The balls are 17mm wide. You can use a marble.

kossel

No

No

0.2

25%

I use a hair dryer, to carefully hot the thin part of the ball support and then insert the ball on the hole. Once the ball is in I press the plastic walls against the ball.