Oil pump gasket?

Melling supplies a gasket and Mancini sells one. I took this pump off another motor and it did not have one. There was a post on here that a member was investigating a rear oil leak. He found this same problem and filed the surfaces flat and re-installed and the problem went away (maybe he sealed the pan better). I personally would not take the risk of metal filings getting in the engine even if it was cleaned. Looks like to me these two mating surfaces if not sealed could cause oil to run out. This motor makes 60lbs at idle hot and 70 on the highway. I'm considering the gasket. Amazing how some things get taken for granted, that machined surfaces are always parallel and true. Not so here. I'm going to use a feeler gauge and check the main cap and the pump today with a straight edge and report back. Thanks all for your input.