Peter Perry,
Put them on eBay.
A few years ago, when I changed my driver's door from a 230SL door to a 280SL door (yes there is a difference internally and externally), I pre-announced the availability of the old door--which for what it's worth, had a flawless 568 Signal Red paint finish. I did this as work was being done on my car.
Not one inquiry. Crickets. Nary a question or anything here over a period of months. What was curious was in the two year project of finding a replacement door, what I found were a number of passenger (RH) doors but no driver (LH) doors. Thus it did take me about two years to find one, and only through the care and concern and good memory of a fellow member here who spied one on Craigslist in the NYC area.
I put the old door on eBay and it sold in a heartbeat. Not too many people here looking for things.