
Looks rather similar to the YEP-321 for which Denis Wick made his 4AY model. I have used the for my B&H Imperial baritone, my 3+2P de Prins Saxhorn basse, my Kanstul G baritone, my Besson G bass trombone, and probably a few more since 1978. The silver plated version lasts longer than the gold plated ditto.
V. Bach 3 is slightly wider, but not as deep, resulting in a more trombone like sound. The Bach 6 1/2 A would be a very common find, but is somewhat smaller. Bach makes the G bass cups with small stems on special order.
I haven't tried the Schilke 51D, but that model is often mentioned in contexts like yours.
Klaus Smedegaard Bjerre
