Heater core coolant shut off valve

[Timinator]

6th gen mirage:

I am looking into a heater core shut off valve, I know some of my old vehicles had them, and the AC is ice cold with them closed...I posted on FB about it, but can not find evidence of the valve mentioned. I am looking to install one of these bypass valves, probably from a ford ranger, and only turn it 'on' in "winter" being I live in south west florida, I am much more desperately in need of cold, than hot haha