My hunch is that the sign is in some rich Germans house by now. Stolen to order. A few years ago a German was arreste for attempting to steal one of the oven doors. The Germans seem to have a sick fetish regarding their death camps.
Just like we long for the good old days..
I was stuck by something when I read your post. Why does Austria get a pass? Yes it was part of Germany during the war, but in fact, per capita more Austrians participated in the Holocaust than Germans. Even before the Anschluss, the Germans had to tell the Austrian Nazis to tone it down a bit. Not to mention of course that Hitler was Austrian.