Found this link, wanted to share

http://batinc.net/aston.htm

http://97.74.32.155/files/cap2.pdf

Mario

Found these on ebay, the price is OK but there out of cast Aluminum & from India.

http://www.ebay.com/itm/MONZA-CAP-2-...item3cf18fb5d9

There are ones available in either aluminum or stainless from Keith Eickert or CP Performance

http://www.keperf.com/c-492-fuel-fills.aspx

http://www.cpperformance.com/c-492-fuel-fills.aspx

The original gas fills were chrome over bronze, and
had a 2 or 3 inch neck.Just sold my last pair to a Magnum afficano overseas
Bud a

I've snapped up a couple originals on eBay. They come up once in a while if you watch.
Chrome over brass.

Had four, but they are gone. My stock of vintage and reproduction parts are getting smaller, should publish a list of what I have left. Bud