It looks like a Solo Carola tracker bar.  The first time I saw one
of these was at John Lloyds in Blackburn, a suburb of Melbourne,
Australia.  This is the city where the film "On the Beach" was made.
The city prompted the comment from Ava Gardner that "Melbourne was
the best place to make a film about the end of the Earth".  I also
believe that the first time Harvey Roehl saw one was the same piano.

The Solo Carola was quite rare and I'm not surprised that many of our
American friends have never seen one -- Melbourne is also the best
place to see a rare American design pianola!

Paul Rumpf