need an ac evaporater for in heater box (73 only)

i need an ac evaporator for in a 73 duster. preferably from a running car thats being parted. i want one from a 73 because it has a one year only part #. and i want it to be correct. will consider whole box if priced right. im working on getting this car on the road by spring and this part is holding me up. price plus shipping to 17813 please. central pa. thanks,mike.