Your best bet may be to buy another Carcano for parts. Here's one for $40---and it's pretty much complete.
Unless the gun has some serious sentimental value (your favorite uncle brought it home from WWII??) or you just want
to try your skills at gunsmithing on something that's no great loss if you botch it, there are better choices out there.
Carcano ammo is a bit hard to find, and it's a bit pricey. The ammo clip (yes, not a magazine) falls out after the last shot,
and the safety is almost as much of an abomination as the one on a Arisaksa. The Carcano's only claim to fame is that it
is probably the last military issue rifle ever to use gain twist rifling. (well--that and the Kennedy thing)
If you really like the look of old military iron, Mosin Nagant, SKS, Hakim, Mausers in 47 flavors, the SMLE and lots of other options that
are not crazy spendy or hard to feed might be a better choice.