I would like to take a guess at the mystery player action [000915 MMD].
With the description provided it sounds to me like a Schultz.  The
"tracking mechanism" tracks the spool ends, as opposed to the edge of
the roll, and it sits in the top of the spool box.  It has round metal
tracking "ears" on the ends of the bars.  Anyway, my two cents for what
it's worth.

Diane deTar