Kluczbork is 50 km NNE of Opole with (1981) 22.521 inhabitants. it
was formerly in Germany, assigned to Poland by Potsdam Conference 1945.
Here are the images of the flags and coat of arms of the county of
Kluczbork. It is the answer of the county office to my question. The Coat of Arms
on the flag is derived from the main town, Kluczbork
(German: Kreuzburg in Oberschlesien). There is also an image on this
site.
Jens Pattke, 25 Oct 2001