are looking for. The steering knuckle that connected the steering column to the rack or the front suspension knuckle? Since you mention kingpin and hub I'm assuming it's the front suspension knuckle. I have several used ones of varying mileage and condition but all are straight. If you want to drive up here you can have it for free but I'd rather not deal with the hassle of shipping something so large and heavy. If it's the steering column knuckle I can ship that.
I'm not positive but I believe they are all interchangeable.