I bet your oil pressure sending unit is up top behind your distrubutor cap. There are plugs down by your oil filter where you can also mount the sending unit. It will give you a higher reading but it can leave it more exposed to damage.
With your oil pump; you can change the spring and it will bump your oil pressure also. I had same problem you did with low oil pressure so i replaced my pump with one that has higher pressure. Now oil pressure is a little too high. 75 when cold.