presure!, low oil Options

[6gc_ct]

Getting disturbingly low oil pressure. brought the car to be diagnosed, one of my issues was that after driving for half hour maybe longer, at IDEL rpm only, the oil sensor light would come on sometimes just flicker. mech called me and told me that at 3k i was only pushing 15psi which is damn low. i dropped my oil pan yesterday to have a look see and everything looked ok. my bearings were tight, that and i never had any knocking noise while driving. my pick up screen was clean and clear. only thing i can think of would be oil pump but how could i tell without pulling it off?

[6gc_ct]

motor doesnt have much mileage to it just rebuilt it last month, maybe two. but it was burning oil bad before i rebuilt (at least 5 quarts within a week) so i was thinking maybe oil pump is worn out from being low on oil at times. I dont have a problem buying one, but just rather be pretty sure that guessing thats the problem as i just put down cash on rebuild costs. im sure some of you guys can understand lol.