If you just need the cancel cam, they're available as a separate replacement part. If you have any electrical problems, you'll need the whole switch assembly. There are several to choose from from the usual restoration sources and on E-bay. Factory NOS parts are a known quality but you'll probably have to pay more for one. The aftermarket ones I've used through the years seem to be holding up fine too so unless it has to stay OEM for some reason, give a repop a try. I think the last switch like yours I bought was from Van's on E-bay.