Unfortunately my sources are pretty bad - Mileta, the only textile company still running (afaik) has this info on its website. It was easy to confirm that it's true (by that I mean the fact that there were several running factories at some point) by googling and finding some mentions here and there, but nothing more. According to a historical postcard, one of the factories was called "EM. FEUERSLEIN A SPOL", but again, no more information to be found. Towns around here often have tons of historical records in their archives or in local libraries that would surely contain useful information, but it's almost never digitalized (=takes a long time to search through it, it would also obviously be in czech or german) and may not be easy to get to.