Hi:
You need a gauge to check the oil pressure. It screws into the same spot the sending unit is. Many parts stores will lend or rent them, so I would check that. Also, oil pumps usually last a long time if the oil has been maintained. However, that doesn't mean they can't. Chances are you have a sending unit problem unless you hear internal engine noise like bearing, lifters.
Let me know what you find or if you have other questions.
Joe
Friday, February 13th, 2009 AT 8:50 PM