When I need anything metric (automobiles use a lot of metric fasteners of various sizes) I order them from BelMetric.com [0].

You can order one or one hundred or one thousand and they assemble your order and get it out to you faster than any other provider of fasteners that I have used.

They have an excellent selection including specialty parts that might be useful for building telescopes.

https://belmetric.com/

They're the best.

Overall this looks like an interesting project that is not difficult to make. I may need to level my printer bed and see what happens.

https://www.youtube.com/watch?v=NA076d-gsyY

Also wrote it up on my website, which has a link to the Hackaday article I wrote on it: https://miscdotgeek.com/3d-printing-the-hadley-114mm-newtoni...

I still need to build a proper base for it. Balancing it on a chair or some other thing is just no good. It needs to move smoothly. What you think you know, don't realize how pronounced it is until you're watching through a decent telescope, is that the cosmos are on the move!