Quoted from underlord:
Sorry, Home Depot.[quoted image]
Quoted from Join_The_Cirqus:
$0.88 at walmart[quoted image][quoted image]
I don't believe those generic "caster cups" fit "tight" enough to stay attached to the leg leveler when you lift the game up (e.g. to adjust level of your game, or to move it a few feet). I used to have some of those on a game and found that very annoying.
The ones PinballPro is selling do stay attached to the leveler, even if you lift up the game, and are much better for pinball.
All IMHO of course, YMMV
Ps: Europeans can buy them here: https://www.pinballshop.nl/cabinet-parts/legs/leg-leveler-rubber-castor-set-of-4