Dear Christian,  Just have a look at the musica mecanica web pages,
and you will find the address of a good museum of mechanical music
in Finland (I just hope it is still in existence !).  In case you
do not have access to the web, here it is :

  Mekaanisen Musiikin Museo,
  Pelimannikatu 8, 78850 Varkaus, Suomi-Finnland,
  Tel.: (00358) 72/162611
Directeur: Liisa et Juergen Kempf

Best regards,

Philippe Rouille  (Paris, France)
http://www.musicamecanica.org/