Water Valve Assembly

This is the water valve assembly that was mounted on the fender well in the engine compartment on my Dart. I believe the water valve itself that the heater hoses connect to is frozen so that it will not work. The vacuum valve portion of this assembly seems to work. I am wondering if anyone has this replacement assembly? Or is it possible to just replace the water valve portion of this assembly? I appears that the linkage that attaches to the vacuum valve could be taken apart, but it appears easier to just replace the entire assembly. Let me know if you have something. Thanks.