Questionable 3 speed fan connector

The plug in for the 3 speed fan switch for my 74 Duster AC still works but you can see that it has overheated and the metal contacts in the plastic connector are fused together. I want to replace the plug in connector, but should I replace the switch and the fan motor? I am getting my AC system back in working order and want to make sure all components are in good shape. Does the partially melted plug in signify a problem or just due to age? If anyone has any of these parts or know where to find them it will be much appreciated.

Thanks. Gary