The pressure sender that I recently got to use as a fuel pressure sensor turns out to be a 3bar sender, which is basically useless for EFI.

A oil or fuel sender will work fine as long as it meets these characteristics:

1. 5V ref. I prefer a 4-wire version (as it will be mounted in an ungrounded location) but a 3-wire will work, I suppose as I could somehow ground it. I.e., the wires should be 5V sender supply, sender ground, signal + and signal -. A resistance sender will not work.
2. This should be a 5 bar sender or 1-100 psi.
3. Standard 1/8 NTP. I dont think I have ever seen other than this, but whatever.

Any info on where to get such a sender new for less than about $50 would be great as well.