Tire valve caps

[Greenstude]

I would like to buy 5 brass tire valve caps, as used in the 1940s/50s, either new or good used. Could someone suggest a source, please?

[Carl Purdy]

http://www.extair.com/brass-valve-stem-cap.html

[JBOYLE]

I've never thought about those for my Avanti....
As a kid in the 60s, I seem to recall the caps were black plastic/rubber.

Anyone know what they would have been fresh from the factory?

[BobPalma]

Black plastic, John. BP