I had a pressure relief valve hang open once years ago because "crud" got into the engine and made it stick open. (don't ask).
Anyway, It was driven off and on for about a week with low/no
oil pressure. Once I fixed the valve the car was fine for many years after that and in fact when I sold the car, I still had no problem with the engine. It was a GM 3.8 V6.
So, why not fix the relief valve and see how it runs. It might be fine. What is the
oil pressure now?
Even if damage is done it will usually be the bearings. If that is all that is damaged and the
oil pressure is truly low, just pull the pan and pop in new rod and main bearings right in the car.
Ed