This surprised me
MELINGRIFFITH CADET CORPS CAP BADGE.GOOD SCARCE DIE-STAMPED BRASS WYVERN ON TORSE. CRIMPED
£220 with no attribution to a cadet unit in any reference work I know of. It had a band which has several photos on here
http://melingriffith.co.uk/about/history-of-the-band/ but no wyvern in sight.
The Wyvern is a English/ West Country related beast and not a Welsh Dragon which would be more fitting for a South Wales unit.