So, does the static noise only exist on Channel 3? Is the turntable silent on Channel 1 and no static noise.
Static noise could be a few different things, it's really hard to say without more details. How are you grounding the turntable?
You cannot just replace the phono amp, it's not on it's own card and is part of the main PCB, if there is something wrong it's more than likely just a capacitor that needs replacing, though making presumptions like that without thorough testing is guesswork.