Hello,
Warren Carroll's book "Eagles Recalled" illustrates a number of examples of original RFC metal wings.
See also
http://www.britairforce.com/other/RFC_Metal_Wing.htm including the link within the page to another site.
The majority of the ones that are on offer these days are reproductions / fakes, albeit some appear to be struck from an original die.
It's defiantly a case of "Buyer beware" when it comes to these types of RFC metal wings.