yeah i c. in that case ill have to see if i cant find anything at the hardware store. cause if i can find anything, they would probably be something like a cpl of cents a piece.and if i can find anything like 6x...x0.2mm im good. doesnt have to be 19mm outer diameter. Just inner diameter and thickness has to be right. the main purpose of that washer is to make a proper seal with the o-ring to prevent the fluid from leaking out. But of course u cant run without it since it would throw off the mesh of the spider gears, and cause the diff to leak.