Don't get it right, just get it running. 85 318 roller

I agree 100% about reusing the oil pump. I've never in my life seen an oil pump fail all on its own. Something else always caused it. They live their life very well lubricated. lol What I WOULD do though, would be to get a high pressure oil pump sprAng and install it. With an engine with some mileage on it, that's certainly not a bad idea. Cheap enough, too.
https://www.summitracing.com/parts/dcc-p3690944