Hey
@onlysleeping, here's what has worked perfectly for me, YMMV.....
Find an old set of earbuds and carefully remove all the wiring. If it has a volume control, just use the wire from that control to the plug as it will still be plenty long. My experience is with Apple earbuds, so it's possible that others may not work as well, but I found those to be copper Litz wires and a fantastic choice for my Nottingham Analogue Studios Spacearm that needed re-wiring. And further good news is that since I don't wear earbuds, it was a free alternative to the prices many are charging for that kind of wiring these days. The advantage of using such fine, hair-like wiring is that the movement of the tonearm is not restricted so you're not causing other problems as
@JP has warned about above seconded by Sarge.
A challenge you will face is the removal of the very thin coating of insulation at the ends where you will be soldering your connector pins on the one side and the RCA plugs on the other, unless you are going to a block of some sort but you'll still have to deal with that coating. Some have been successful just using the heat of a soldering iron to melt it off and I suppose that would work although my efforts have been more successful the old-fashion way of stripping it back, which can be done but fair warning, you will need to move very slowly and use a light touch, preferably wearing some magnifiers so you can see when the wire is bare. I "rolled" the wire under a razor blade just slightly to get a weak spot and then remove it with my fingernails. I did fail a few times at first until I got just the right touch, but I had plenty of length to work with, as will you, so it was just a matter of learning the process. It doesn't take much to get it to come off after you create that weak spot, but even the slightest bit of too much pressure on the blade and you're cutting wires and will need to start over. I don't remember exactly what the resistance was right now, but I do remember it having been identical or nearly so to the silver Litz that was in the tonearm originally. I could tell no difference in the sound, and that's the real winner!!!
Good luck, and let us know how you go amigo!