Ok I know we're all very busy being spooky right now but when the heck did JLCPCB add "mechatronic components" to their catalog??? Including what looks suspiciously similar to the most popular parts of SMC's pneumatic line???
https://fa.jlcpcb.com/
It's like McMaster, except with a 3-week budget shipping time, fantastic prices, much worse documentation, and custom assembled PCBs. This rules.
they even carry my favorite brand of leveling casters! At competitive-to-amazon prices!
https://fa.jlcpcb.com/productdetail/D18_GDN-40-S_NYN-CEN
And the hard-to-find ratcheting variant thereof:
https://fa.jlcpcb.com/productdetail/D18_GDR-60-F_NYN
And if those are too rich for your blood, they even have the slightly-flimsier chinese-manufacture version (the FOOTMASTER ones are korean):
https://fa.jlcpcb.com/productdetail/D18_DEPA-W2_60-N
seriously I cannot recommended these things enough. I put them on everything. Like, including my desk, including the rack I keep my "desktop" in, including my 3D printer rack. genuinely the best. If you've bought cruddy casters before, and wondered if you were missing out on something: you were. These things have ruined every other locking caster for me, because none of them lock as solidly as just extending the little feet down on these.