Just order a new one, I had to find 3 for some core tranny's I'm rebuilding. I searched long and hard, used ones just aren't out there for the 4500's. I got lucky and a friend at a large jeep store with New Venture connections had a NOS shaft sitting on a shelf for years. That one is going in my personal build, I ended up having to order the other two (one early, one late) from Standard.