You can't mod them by wearing down so most likely it has been touching the pulley, which will kill it of course.
Any of the ford cps sensors will work if you get them fitted, but make sure of gap on ALL lugs ie set gap at nearest highest lug, as if set at a worn down/broken lug the high ones may clout it.
I would imagine the std sensor for that bottom end, is there no number left on it ?
tabetha