Nice looking carbine! From what I can tell from the pics it has a few later-model parts on it - nothing wrong with that as it most likely went through one or more arsenal rebuilds in its military career. For instance, I see a round bolt as opposed to the earlier flat bolt, and a 4-rivet handguard. The rear sight is a later model as well, as the original carbines has a two-position L-shaped sight with no windage adjustment.
You can buy new Korean magazines fairly inexpensively, and they work great. The CMP also sells used G.I. mags that seem to work fine, but may have some surface wear and possibly a little corrosion on them. Gives 'em character, though.
I advise you to stay away from the Mexican Aquila ammo (sold by the CMP). It's weak and dirty. My son and I have 3 G.I. carbines between us, and all three malfunction with Aquila but shoot everything else just fine. I'm convinced that if we ever go to war with Mexico we'll have to spot 'em the ammo just to make it a fair fight!