I don't recall the 2 dr shell for sale.
From time to time parts and panels turn up that have been used as physical reference by the motor industry and anything structurally sound that turns up as 'new' must have been kept for reasons outside of the norm.
Other parts that turn up could have just been 'forgotten'.....as in Holtmann & Neidergerkers 124 Spider cars & parts haul that started their business...and Mick Woods 131 works car that turned up in Africa with containers of spares.
Just keep looking....you might get lucky