I used fiberflex gasket material and a gasket maker kit to punch out the washers. You could go to an automotive supply house and purchase a small sheet of fiber gasket material. The thickness is about 1/32" and seems to work
. I found no thickness specification so it's a guessestimate on my part. I think the purpose is to separate the steel portion of the armature from the bronze bearing in the housing. Hope this helps.
The other Rodney