>[ The original Tangley players I've seen with unit valves were made
>[ by Amphion.  What maker used die-cast valves?

Robbie,  I don't know the term "unit valve", but it might apply to the
fact that each player valve and its key bellows are a "unit".  These
valves are about 1-1/2" wide by 2-1/2" with an adjustable cover glued
in place.  The valves seem to be made of die-cast carburetor metal.

I'm certain the valves are original. They are old and somewhat fragile.
The gasket under one of these assemblies had "Ringling" written on it
in pencil.

Stan Harrison