Not sure but I've been looking for a JP machine for a while now, I noticed on a few in rough condition that they need decals. I'm not sure if they exist I tried looking for them.. If you come across them please post a link. I know that supposedly a plastics reproduction set should be available eventually *at least according to this site :
I'm pretty sure that Jeff at Classic Arcades now has JP insert decals. It is usually best to contact him through his eBay store. He will also break up sets if you only need one or two.