High Volume or Standard Oil Pump

[mattpiotr]

I'm rebuilding a 350 4 bolt main motor to put in my truck the blocks a 69-79. Everything is all standard no boring. the motor has a mild comp cam in it and thats about it. its a 2500 truck I use it for a everyday driver. pull trailers, Plow snow with it and drive high ways. Before I start to put the motor back together I just want to see what oil would be better for me. a standard oil pump? or a high volume standard oil pump the motor has the 6 qt pan in it. The motor that is in there now when i do 75mph on the highway the oil pressure downs down to 15psi. I don't want this same problem with the new engine. Thanks