Oil pressure sensor, EJ20 99-00 - Where from?

I'm looking for a standard oil pressure sensor (on/off) for a 99-00 sti EJ20 but I don't have engine numbers and stuff so the local main dealer will laugh at me.

Where do I get one from? Done a search on ebay but not seeing anything.

Thanks Al

 

Is it the one under the alternator if so I got one from my 1999 uk2000 if same?

 

25240KA040

From here for example.

But breakers will probably do you one for peanuts