Change oil pump while replacing pan gasket
I would replace the oil pump, timing set, and toss a new water pump and thermostat at it too but... We're not talking about my 96 Camry daily drivers. Yeah 2 of them, mine and grand daughters. Both show nearly 300K miles. The way I see it, if it takes me 8 days to get'er done, the labor is free. Total part cost is less that the average monthly payment. In the end I've looked at belts, hoses, replaced everything in questionable condition. I sleep better thinking I invested in dependability, got ahead of tomorrows "hood up".
I wont go on about cheap aftermarket parts, my hard lesson learned, just to say it was the oil pump.
Alas, hood up again almost exactly a year later. Had to pull a good portion of exhaust to replace 2 little water hoses at a oil cooler thingy under the oil filter. It's more common for that cooler to leak oil and need reseal. Both cars running OEM hoses there. Neither leaking oil. Of course I purchased oil seals, gaskets, hoses, all times 2, planning to do the same job on other car. Hopefully before a failure ( fingers crossed ).
So we can't replace everything from radiator cap down. We can't predict whats next. We can know what is not next. Best of luck with yours.