Just my two cents worth on donating music machines to museums: Don't!
I've had some experience working directly with museum staff and found
it to be little more than depressing.

First, they have no money so they won't maintain the instrument.  They
may, in fact, have one of their own staff tinker with it, making things
worse.  When it's played it will sound awful, leaving an impression that
"it's just what these music thingies sound like".

When it finally goes silent it will just sit there, and sit, and sit...,
behind a velvet rope where it will be a momentary curiosity for about
15 seconds as patrons pass by to look at something else.  Eventually it
will end up in the basement where thousands of other items are stored,
and will remain there until the institution has a fund raising auction.
It's anyone's guess what happens next.

If you just want it to go to a loving home where it will be appreciated,
then give it to a younger collector who has the sense and responsibility
to take care of it, or else give it to a trusted family member who is
willing to officially declare it a family heirloom to be passed through
the generations.

Museums seem like a safe place to deposit things but sooner or later,
when they stop working, they are doomed to the basement.

Rob Goodale
Las Vegas, Nevada