'78 Spider Oil Pump Questions

[Rattbat@xxxxxxx]

I just finished placing an aftermarket oil gauge below the dash of my '78 Alfa
Spider.  I did so because the readings seemed low and the oil warning light
was coming on during idle.  However, the gauge seemed to be giving me accurate
readings: at idle it is 7, driving it averages 40, and the highest is 50.  I
have read that the factory expects it to be 7 to 14 at idle, and 57 max.  Even
these readings would tend to worry me a bit.  

Here is my question...If I replace the oil pump with OE, what kind of readings
can I expect?  Will it end up being the same?  What are some opinions, should
I be worried with the current readings?  Is there anything such as a high
volume oil pump?  Where do I get it from?

Some background, the engine seems to be fine, and only has 50K original miles
on it.  I have recently, changed the oil and oil filter, and even added STP
oil treatment to thicken the viscosity.  Still the readings are what I've just
stated.  Any helpful information is appreciated greatly.

Thank you,
Frank

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