Before Kev mentions it, I will:
http://cafesaxophone.com/showthread.php?3022-Arta-Guban-tenor. Summary: there may have been more than one company making these. Possibility of production from Czech manufacturers, but possibly Julius Keilwerth, too (which was, at one time, Czech). If you go to
http://saxer.org/luxor.shtml, you get a horn that looks considerably different, much newer and that could actually be from B&S or Weltklang. The other interesting thing is the mention of Klingenthal, which gets me in the mind of Hammerschmidt. There also appears to be a strong possibility that they were made by ... Arta Guban Timisoara in Romania. There are a lot of Russian-language websites (like
this, for instance) that talk about this horn. One would assume that you'd get lots of Communist Bloc horns in Russia, so "Romania" could sound right.
Personally, I think that the Luxor that I mention, above, is overbuilt too much to be a Keilwerth. Helen, if you said "Dorfler and Jurka," I would have definitely agreed: to me, D&J horns have always looked like the Hummer H1 version of the J. Keilwerth horns.
There's another interesting Luxor at
http://www.woodwinds-and-brass.de/html/saxophones.html. There are a couple closeups of the engraving around the bell rim and the rather interestingly designed octave key on the neck.
Anyhow, it's definitely go a bit of the JK look going for it!