Oil pressure and oil flow are different. We don't have an accurate measure of flow so we calculate a pressure range that should provide adequate flow. You are in the safe range albeit at the low end. Anything you do to help alleviate one of your "stacked" causes for this will help bring those numbers up. Here is some math for you to think about that will vary based on how much you do yourself and how you value your time. How much is pan, pump, and labor? How much help will it be? How much for bearings(main, or rod, or both), and labor? How much will it help? Do you trust your builder and his reputation?