Advice from engine guys, please.

[Higgs boson]

What is the likelihood of an engine that has been run extremely low on oil, and presenting with a bottom end knock, being partially rescued by just fitting new bearings, and not changing/regrinding c/shaft?

For completeness, BMW F20 116i. Low oil light did not, at any stage, illuminate.
When level was checked via interior control, it showed as full.

Car was bought from non-BMW source, and was serviced before collection, approx 9k miles ago. Currently with 48k miles.

[Higgs boson]

Little Pete said:

I would also be concerned at the condition of the camshaft and associated bearings and/or cylinder head.

This was my other, unvoiced, concern. I think that an engine from a breaker might be required!

Thanks to all for the replies.

[Higgs boson]

Although I've done the vast majority (99%) of maintenance work on my cars/bike for the last 40 years, the last crank that I had in my hands was from a 250 2 stroke twin, in, I would guess, '81/'82!
I'm not sure how much visual scoring I'd looking for. Colouring? Would I need to resort to Plastigauge?
TIA.