First thing that comes to mind is that Chateau de Gudanes is right in that area, owned by MNC friend Karina Waters, an Australian lady (her story here). She has offered summer workshops and antiques tours alongside the chance to stay at the chateau, so it would be worth contacting them to see if they happen to have something on the program already.
If not, another chateau of note further east welcomes guests, the Chateau des Ducs de Joyeuses where you’ve got Carcassonne and the “abandoned village” of Rennes-le-Château nearby.
