This is actually the company that makes the aftermarket panels. The price just went up in the last few weeks the were $119. The company did sell them on ebay for $119 but they no longer do and they jacked the price up. Go figure inflation...
Here you can buy rear panels new for both fastback and convertible
Fast Back
http://www.laurelmountainmustang.com/products/1971-73-quater-trim-panels-fastback
Conv.
http://www.laurelmountainmustang.com/products/1971-73-quater-trim-panels-conv-dot