Dumb question on Oil Pressure

Alright gentlemen, the final thing before I crank the new motor is the oil pressure attachement. On the back of the 350 behind the dist. there is a little plug for my gauge to read the oil pressure. It looks almost like a fitting with sone copper tube coming out. Where can I get this, all local part stores are tring to give me an electronic unit which is not what the truck had on it. Can anyone tell me what it is and where to get it?

It is the oil pressure line for a manual oil pressure gauge.
Any good parts place should have a oil pressure line kit for a manual oil pressure gauge.
Some are plastic line and some are copper.
The Plastic line works good and will not break but watch and do not run it close to anything hot.
MT

AWESOME, thanks!!