Oh yeah, those were discontinued. I don't know of a current replacement. Raid a junkyard pump- that's about it.
The sensor's job is to warn the ECU to goose the throttle a little when you make a sudden move on the steering wheel, to prevent the extra steering load from stalling the engine. That's it, that's all it does as far as I know.
I went to a salvage yard and got the part unfortunately I had to buy the whole power steering pump assembly $35. On the other hand I have been looking for a replacement bolt for the alternator and the bolt came with the power steering