stock 360 oil pressure is
13 PSI at idle is fine. Things to watch out for:
Oil pressure not up to "normal" by 2500 RPM or so. "Normal" is where the pressure levels off due to bypass opening. Typically 45-50 PSI
Oil pressure dropping at higher RPM's this is a symptom of excessive rod bearing clearance.
Using a heavier oil to bring pressure up. The pressure is higher due to the oil's resistance to flow. The idea is to get oil flow, not see how many horsepower you can waste spinning the pump.