Oil Pressure?

I fired up the '67 Sprite project last week and I have no oil pressure on the
gage.
I don't know if the gage works or not since the car was dead when I bought it.

The engine came out of a parts car approx 1 year ago and had 50-60 psi @ idle
when pulled

What could have happened?
How can I be sure oil is or is not flowing?

Tommy
70B - daily driver
67 Sprite - Running but scary