As Dan said, mine is newer model than yours and more readily available.
IIRC, (Dan or others can correct me here) the switch model that fits my '75 Dart was used in another form (with the turn clearance light output) into the mid-late 80's.
The switch I bought is Chrysler OEM and was a perfect fit. It does have the clearance light output but I left them pigtailed up under the dash since I do not have those lamps.