Art Deco Halloween Witch on Broom Metal Panel - Needs TLC

Dating to the about the 1930s, here's a lightweight metal (tin?) panel that I believe was once a pinback to wear during Halloween.  The front 3/4" round has a very good strike of a witch riding her broom; at the end of the broom is her pet cat.  The reverse shows a long line with traces of lead solder - this would have been where the pinstem was.  Overall, a very unique find!