I actually found them at a local True Value, but I also saw those at Lowes. They look close to me.
I used a dial caliper to measure the original washers. By my measurement they are .544 OD X .040 thick X .120 ID. This is in inches of course.
I don’t have trouble with the washers. I can’t figure our where all of the air is going once I got it assembled.
Let me know how you make out.