25-note Glockenspiel in a wooden case

[anton_liashko]

I own a historical 25-note Glockenspiel in a wooden case, which I believe may be a German instrument from the early 20th century.

The manufacturer is unknown, but one of the plates is marked “870 SCHW”. I would like to have the instrument identified, dated, and, if possible, assessed for its current collector value.