These are the only things from that era that I've found on paper.
From 1902:
Don't have dates for these:
The text on the left side reads:
Established in Manufacturing 1876.
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D. GRUEN
WATCH INTERESTS:
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Watch Factories:
D. GRUEN & SÖHNE
Glashütte by Dresden, Germany,
also Switzerland
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Case Factory:
GRUEN NATL WATCH CASE CO.,
Cincinnati, Ohio
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U. S Distributor:
D. GRUEN, SONS & CO.,
San Francisco Cincinnati New York
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RETAILED ONLY THROUGH ACCREDITED AGENCIES
The Leading Jeweler in each city.