I did a little research and found a heater blower motor identical to the old one in my 1980 Avanti. Only difference was the connectors on the wires which i modified to fit the original plug connector. Even the wire colors were correct for the 2 speeds.
Price $89.96 on Amazon. Maybe I could have gotten it cheaper elsewhere
I found it on Amazon but i am sure it can be had other places. It was made for a 1960-65 Falcon, 1964-65 Mustang and a 1965 Comet without A/C.
The one i bought was made by Auto Krafters, part number CODZ-18527A but as long as you get one for one of these cars, you should have the correct one.