What replacement sights for Norc NP22?

[Silveragent]

I somehow missplaced the rear sights for my NP22 (Sig P226 clone) a year past after I got a red dot put on it and then taken off. I'm probably never going to get rid of the Np22 (and certainly can't sell it without sights in any case). What should I put on it? Intended use is just as a hardy backup gun (first one is a CZ SP01). Not going to compete with it, just a second gun.