Ya the 2.5x foresters with the cable model heating systems are a pain to change the radios in but the cables will come out pretty easy if you unhook them at the heater box by your gas pedal and the same on the other side it just a pinch clip that holds the cable and then a eyelit on the end that...
I have a couple kicking around that you can listen to and pick which one you would want they aren't low miles but they are good running 2.5L they are 01-02Ish for years