There is a very nice, albeit small, collection of mechanical music at
the National Technical Museum (Národní Technické Muzeum) in Prague.
Since the collection is not always on display, a pre-visit telephone
call to the curator might be a good idea.  Below is a description of
the collection which appears on the museum's web site.

Dick Kahane

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Quoting from http://www.ntm.cz/en/collections/exact-sciences :

Musical machines

The first musical machines appeared in the collection in 1929.
Systematic acquisitions were made in the 60s when the collection
received its rounded-off character.  Currently, 119 musical machines
are deposited in the National Technical Museum.  The collection is
systematically divided according to the principle into glockenspiels,
pipe machines, comb machines with barrel and disk, reed machines and
combined musical machines (orchestrions).

The collected musical machines were created in the period from the
mid-18th century to the World War II and were manufactured mainly in
Czech, German and Swiss workshops that dominated this field.  The
greatest part of the collection comprises comb machines, barrel-organs
and reed automatic machines.  Rarities of the collection are
represented by the machines with movable figurines: barrel-organ
with a boy figurine (Polyphon 1894), barrel-organ with an ape band
(Netherlands, 1840), a Negro playing flute (Halle, 1900), automatic
machine with puppets Amorette (Leipzig, 1890), cylindrical music box
with Chinese, automatic machine with bees (Switzerland, 1880).

Pieces made in Czech workshops are represented by comb musical machines
and production equipment from the workshop of Frantisek and Gustav
Rebiceks from the last century.  The collection of barrel-organs from
Prague (Hrubes, Kamenik, Rubes) and country workshops (Gall - Hostinne,
Reimer - Chrastava, Kolb - Pekarov) is quite numerous.