When I replace those wave washers, I use stainless steel washers @ approx .50 each. I believe the technical name for those washers were machine bushings. An old fashion hardware store is your best bet. Match up the inner diameter of the wave washer or the shaft diameter to get the right one. You'll want to use a thin one, about 1/16 of an inch thick at the most. Grease them good when you install them and you'll never replace a wave washer again. That use for them is to force the plastic covers apart from each other so no rubbing takes place and the arms firm up during use.
