We are out of stock. You can order one online at Napa. Or go to your local Napa parts store. Part number is 703-1698. That one is 16 PSI.
Carquest has a 22 PSI unit for $5. Part number is 10235.
This cap is only about $5. It is silver, and you might want to paint it black with some flat black spray paint. Also, it has no chain. You could drill a small hole in the edge and attach your old chain if you have it. But it seals fine and works well.