Reddit mentions of uxcell M2.5 x 6mm 304 Stainless Steel Phillips Round Head Screws Bolt 60pcs

just to expand on my other post because I didn't have all the links at the time. Hopefully this helps others too. Feel free to add to this if there are better solutions than these.

MeanWell RT-65B power supply keep in mind that the -12v rail is only good for 500ma. check your modules in modular grid to make sure you don't need more than one of these power supplies. it's super easy to wire the power supply to a busboard but if you don't feel comfortable doing it you'll have to get something like a Zeus power supply.

Vector rails TS-600 is the best value if you are building a large case or want to build more later or if you want to sell your leftovers on Reverb or whatever. You can use these screws to attach the vector rails to the case or the spacer strips.

Rail nuts these are the square nuts that slide into the rails (only for vector rails) they require M2.5 screws 6mm is a good length unless you have some thick acrylic panels on your modules or something like that. you can alternatively use threaded strips but they will cost a little more and I'm not a fan. Not all modules have their panel holes in the appropriate place and sometimes it causes a problem because the threaded insert holes are fixed in one place.

Panel mount plug w fuse you'll need to do a little wiring on this one. match the fuse value to the power supply overall amp draw. Don't go too much over. the fuse is supposed to blow if too many amps go through the case. Having too large value of fuse defeats the purpose.

I like this busboard and they also have the cheapest (Warning! see edit) 3U sideplates although I don't see why you can make your own or maybe even go without them. MDLRCASE actually has some great values on the larger cases too if you decide not to DIY. If you are in the USA shipping is quite an expense though.EDIT: the 3U side plates do not work for vector rails, they are the wrong spacing. They only work for the rails which they sell which are different. So, if you are using vector rails, don't buy these. The busboards are still cool)

If you decide to go for the flying bus cable

build notes:

Each 3U (height of one eurorack space) is approximately 5.25" (133.35mm) but the modules are mostly less than 130mm tall. so you can build the height of a 3U rack so the the interior dimension from wood to wood is 5 1/4" exactly and you'll be fine.

Don't cut wood until you have your rails and spacers or at least rails and a blank panel or module installed so that you will know the exact width you will need for the rails.

Be aware of the depth of your modules and factor the space for the power supply and busboard. don't make the case too shallow or some modules may not fit. Modulargrid is your friend for this and the power draw.

There will be wall level voltage inside your case, so make sure you route those cables neat and secure them well. Cover them if possible and don't let stray screws and stuff fall in there. If they do, power off and get them out. Use blank panels to cover unused spaces. Obviously power off and unplug when installing modules.