I've noticed my DU bushings are shot on my glory, nice loose rattle 🙁
shock pic
I've tried to measure this using examples from mojo, tftuned and bted websites.

The tolerance is small. How can you make sure you get the correct size, because replacements come in sizes like 2.89/2.9/3 cm. It's hard to know what's the correct size.

Would any of the above companies know my bushing size for my frame/shock combo? Any recommendations which company to use from that list?

If you just want the bush its a standard Fox ½ inch bush. Have not a clue what it works out at in new money but if you ask them for a Fox fit bush they will know strait away what your talking about.

Edit: Also if your talking about the mounting hardware is the with of the gap and the through bolt size. For example on my Orange is 22mm wide gap and uses a 8mm bolt. Bolts are normally 6 or 8 mm depending on the bike.

AFAIK, all Fox shocks have the same size bushing (Only the mounting hardware varies between bikes) which is a standard, off the shelf, DU bush, and easily available. Fox charge about £4-£5 for them, or you can get them HERE for £1 each. Your choice! 😀