Your local hardware store or auto parts store should have plenty to choose from in stock for very little to nothing.
Tom is right, you want a 1/16'' ID collar
Any hobby shop that sells model airplane parts can provide you with them. They're called wheel collars. You'll want one with a 1/16" I.D.
Tom
I am sure I have a few laying around on my workbench at home. I will look tonight and let you know.
If you have a Volkswagen dealer close buy, they might have them in stock. They were used on the air box/heater of rear engine beatles.
Are you looking for them also?Did you ever find them and how much?