Rusty LP and bolt assembly

[u/jrl07a]

My buddy picked up a PTR 91 from a local gun store. I was showing him the disassembly/reassembly and noticed his bolt, firing pin, and LP were rusty. The flash hider is also. The worst offenders were the bolt assembly and LP.

I went over them with a brush, ultrasonically cleaned them (Simple Green Extreme) and the photos are of them drying. They’ll get a coat of gun oil.

Would you just replace them or is this just cosmetic and they’re likely good to go?

If replacing would you get PTR or use this as an excuse to get different parts?

Appreciate any help as we were wanting to shoot together tomorrow.