Of course Mike contacted the Vienna proofhouse. As you may gather from my post, Weipert does not exist any more, even the adress of Fückert and the location of the former proofhouse is forgotten since 1945. Weipert had about 50 factories before WW1, making all sorts of metal, textile, glas and other goods. Many of them closed down during the 1920s-30s economic depressions, But most fell into disrepair after their owners and workers were expelled in 1945.