An engines oil pump is designed to last a very long time and typically if the car is maintained properly as in changing the engine oil and oil filter every 3,000 miles then the engine oil pump should last as long as the car or truck.
I have a vehicle that has 500,000 miles on it and it has the original oil pump and it will probably last even longer than that.
I don't plan to change the oil pump until I decide to rebuild the engine and engine rebuilding kits come with new oil pumps anyway.
I've read online before that oil pumps last from 70,000 to 150,000 miles and that would be okay to replace the engine oil pump after that many miles because some oil pumps are only $25.00 to $50.00 which is cheaper than a new engine or engine rebuild.
But you must remove the engine oil pan to get to the oil pump and then you must also prime the new oil pump properly to lubricate the engine upon startup and also keep proper oil pressure going through the engine.
I would say that you should get well over 200,000 miles out of a good oil pump but you don't want it to fail and if you see a drop in oil pressure then your oil pump could be going out.
If you're losing oil pressure you need to get the car checked out because without oil pressure the engine will not be lubricated properly and then will destroy the bearings and you'd likely get a spun rod bearing which would then damage the crankshaft and then the crankshaft would need to be replaced or machined.