[GTALUG] Server rack questions

[o1bigtenor]

Greetings

Have an old HP rack (tall think its a 42U or so.

Finding the cage nuts - - - where at a reasonable price?

What else to I need to install 2 old servers and 2 rack UPSs?

I have been looking but am finding that different companies call
things by different names.

Also looking where I might be able to get these things reasonably
(have access to a US delivery address if that helps the costs).

TIA

Dee