I only know there are two German harp builders building e.g. historical harps, Pepe Weissgerber, whose other harps are wildly popular in both Germany and the Netherlands and, Martin Gust, (of Magus Harfen who is having a good name in at least Germany.
Pepe Weissgerber, have a look at: http://www.weissgerber-harfen.de/index.html#trippel (who also builds modern double strung and cross strung harps.
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