Great idea going with wood Ron 👍
When I'm looking for thin-rim nylon washers I'll look around the plumbing/kitchen parts area. .
The boxes of hardware store steel washers always seem to be 1 size larger than advertised. I know that 3/8" has almost a 7/16 hole. Too sloppy for 3/8 and needs a slight ream to be perfect for 7/16. Similar effect on all common sizes.
If I was going to make a bunch of those, I'd have use a hole saw to cut the OD in a thick piece of stock, but not all the way through. Then the pilot hole gets drilled to the ID needed.
Off to the bandsaw to resaw the stock and liberate the washers (just like cutting the tapered hole plugs).