Thanks, AmCruiser: I had not thought of trying eBay motors.
I like the eBay compatibility checker - if it's accurate, it is very useful, opening up many other years and models that I could harvest a part from.
The only problem to be aware of is that there were sometimes incompatible versions in use at the same time. Some of the early Dodge controllers were heat only. Later, options were extra controls for rear window defrosting, and for rear coach area vents. I don't know if the latter controllers could be used in place of the two lever, 6 button controller I need.
Because no-one seems to use part numbers, it is impossible to check for such pitfalls without photographs and knowledge of different options (Indeed Dodge could not tell my mechanic what part number I needed - a salvage yard assistant was kind enough to research the part # for me - that's when I found out about variants). Even the Service manual does not show part numbers!
After finding a part through http://www.car-part.com
I called to verify because the car-parts database did not show there is more than one version and by then I knew that there is. And sure enough, I was initially offered the wrong one. We ended up trading photos, and I hope to get the correct part soon. AND I DID!
A/C working great now......... Thanks to those who kindly contributed ideas!