A Mystery Graphophone Reproducer

[phonogfp]

We've all seen many floating Graphophone Reproducers.  I own quite a few of various designs, including two that are built like this (not shown in Hazelcorn).  Note the lift "fingers" which are seen on several of the Grand Graphophones and the Type AO; perhaps a few others as well, but this variation is too short for a Grand Graphophone.  It fits well on an AO, but the AO was originally equipped with a "D" Reproducer. 

 

What's really puzzling me is that I've never seen any other Graphophone Reproducer marked like this one.  The additional stamped information is filled with black (paint?).

 

I have a theory, but I'd be interested in what others think.

 

George P.