I, too would love to know where to get power switches for both Ampicos
and Duo-Arts.  There were about 3 different models (that I can recall)
used in Ampico drawers before the model B came along.  Two of these
were pull-on switches.

Cutler-Hammer made some of them, and I located some C-H switches, 5A
125 v. pull-on switches for early aircraft use, but they don't work in
Ampicos.  They are very early aircraft-type, and the problem is the
very long threaded bushings and larger size, overall.  They may work in
Duo-Arts.  Unfortunately, it's a 1917 switch design and no longer made,
either.  I had purchased them from an electrical outlet in the East,
somewhere, sent them back, and kept one.

The best solution will be a modified wall switch that is not a
mercury switch (because some mercury switches cannot be laid down
horizontally).  I have looked for pull-on switches for years.

The very early drawer has a type of switch that is extremely small
and can be replaced by a very small bat handle toggle by changing the
linkage.

The Duo-Art also has a pull-on switch and when it's replacement time
for those, we're already having a lot of trouble.  I'm seriously
thinking of doing it with a micro-switch or another small pull-on
commercial switch and relay, by routing out the switch block.

Regarding power MOS-FET switching of player pianos, I'm really not in
favor of any kind of switch that can be destroyed by lightning surges
on a power line.  A piano or orchestrion stays plugged into the wall
at all times and in my opinion, should not be just one more thing that
owners should have to unplug during a storm or before a vacation.

Craig Brougher