$150.00 for the pair with cracks, 2 offers on the listing declined.
http://www.ebay.com/itm/72-Plymouth-Duster-Tail-Lights-
Pair-/330873541696?pt=Motors_Car_Truck_Parts_Accessories&hash=item4d09999440&vxp=mtr
I may have enough left to send your way. If you pm e-mail I will send a pic. Spare tub was cut out but should have the area you need. I am going back half with this one.
Frank
I would let you have mine for free but I think you are in the same boat I was a few months ago. I called the shop that did mine to see if he still had one left, I will post when I hear. Good luck.