I'm living in Vienna at the moment and the most common Austrian bikes of the vintage era are Puch and KTM with Puch the most common. Perhaps do a search of Puch or KTM bikes or wheels and it may give you a match of the wheels or bike. If you were here in Vienna, I'd say just take a walk with a wrench and in a half hour you'd have walked past a half dozen abandoned old bikes with city applied tags saying to bike should be moved or it is to be cut and scrapped.