My 1920 Ampico grand has a 1/8 horsepower, 1150 rpm Holtzer-Cabot
motor.  A smaller, new motor from McMaster Carr is about $160.  Of
course, nothing about it looks like the original, or would mount like
the original.  And, nothing would be tough about making a mounting
adapter.

The wiring in my beast was replaced with lamp wire during its
restoration over 40 years ago but it's hard to imagine that that lamp
wire dates back even that long!  I think most of us would much prefer
our old motor, knowing that it was still healthy and doing its job,
to some tawdry, tin and tinsel modern replacement.  That lovely lump of
cast iron, beautifully finished, properly lubricated, with no straying
insulation, has got to be quieter than a new sheet-metal motor.

It seems to me that worry could be much reduced by adding protection
against excessive heat and/or electrical failure.  If the motor runs
hot to the touch then the issue might well be ill-lubed bearings (like
those I found in my jointer), or the pump, or a too-tightly tensioned
belt.  If it's hot enough to burn something, electrical failure is sure
to follow.

Many motors and power tools have thermal breakers right on the motor;
these things can be found on-line.  Most of those online are stand-alone,
measuring overcurrent like those in your electrical panel, but some can
be found for mounting on the heat source.

Lacking thermal overload protection on the motor, electrical failure
can be contained by using GFCI and/or Arc-Fault receptacles.  I'd like
to think that a motor that got hot enough to burn its insulation and
trip a GFCI would not stay hot enough to burn the piano!

Douglas S. Heckrotte
Philadelphia, Pennsylvania