I have an empty iced tea mix can in my Ikari Warriors. The stock coin bucket was missing, and I had a couple empty iced tea mix cans, so that's what I used. Oddly enough, it sounds better than the original steel bucket in my Super Punch-Out!! machine (which is a heavier steel that doesn't resonate much), and way better than the original plastic bucket in my SFII (Dynamo) machine. Those iced tea mix cans are heavy cardboard with a thin metal bottom, and they resonate loudly when a quarter hits the bottom. I think Crisco cans are made the same way, and no doubt, cans from many other products.
I used two of them, the one I put in first is just a space filler, so the second one, the one that the quarters drop into, can't slide back.