So I recently got a something addiction, and through an unfortunate series of events, the axle got bent. The yoyo still works, but it vibes like crazy. 
I looked on yoyoexpert, and I didn’t see any axles made specifically by something, so I was wondering what axle I should get instead to replace it. Any suggestions?
like 15mm m4
Take it to the hardware store and look for a proper size set screw that fits. If they don’t have one get a regular screw and cut the head off. Smooth the cut edge on a stone or fine file.