oil starvation

[nurspec180sxr]

My car reads no oil pressure. my mechanic and i pulled the oil gears and checked and primed the oil pump. There seemed to be no problems so we reassembled. and still no oil pressure.NOTE. there were impressions left by some matter on the teeth of the gears it looked like a tiny rock or something was in there.

So let me know if i need to do something else or if there is something im missing that needs to be checked. Thanks

The engine is a sr20det in a 92 240sx