...You are confused.
ALL 1973-76 Dart, Valiant Scamp, Duster and Dart Sport models use the same upper door pads. All of them. The doors all interchange but the windows are different. The Duster and Dart Sport have curved glass, the Dart and Valiant Scamp are more straight.
I notice on this 74 Duster You say You are just starting to part out the door mirrors driver door and passenger how much are You going to want for them if You are going to sell them