It does look like nickel because of the shine. Most chrome is brushed or bead blasted. Regardless, the gun would look great, in an unlit room. A cheap refinish to prevent rust would be the most that I would do to it, if it's mechanically sound. I'm a big fan of 45acp revolvers, but that one would make me think twice before buying it. With pitting like that on the outside, I would have to see the innards. Good luck.