Absolutely, go with the 357 Mag!
I like to reload and really think that the 357 Mag has not been given the respect it deserves, since the introduction of the 44 Mag and other "super" hunting cartridges. If you look in some of the really old gun magazines, you will see handgun hunters using the 357 Mag to go after all kinds of game.
If you reload and have a strong enough action, the 357 Mag can be stuffed with Alliant 1600 or H-110 to produce some amazing feats of strength with pretty heavy bullets as well.
If you don't reload there are some specialty bullet loading companies on the internet that sell heavy special purpose 357 loads.
You might try the following:
http://www.buffalobore.com/http://www.bruincartridge.com/Again, go with the 357 Mag it will give you options you will never have with the 30 Carbine
P.S.
If the rifle is for teaching your girl friend and you hope she will use it for hunting. Let me give you some additional thoughts. First, be very careful about semi-autos and new shooters. They can pinch hands and that can create fear and adversion to participating in shooting sports. For new hunters/shooters recoil and caring around a heavy rifle are big no-no's. Many women also have small builds for which standard rifle stocks are a bit long. When it was time to enroll my two young teenage sons in hunter safety training, I had them use SKS rifles, but they had already been shooting 22's for a long time.
I started them out on 22 bolts and used 22 short CB's as the ammo. I also used this approach on some nieces. A 22 short CB has no recoil and no real noise. Therefore, the flinch issues just don't get embedded in the used of this. You can get a cheap used 22 bolt action rifle at most gunshows or pawn shops for $100 or less if you look around. If you are teaching a new shooter, I would start with a 22 bold action rifle that can handle LR, L & short rounds. Start with 22 short CB's and then work up to 22 LR. Again opt for the more expensive short and long rounds over the cheaper LR round, until they are comfortable with the noise and modest recoil. I remember when I was training my sons and neices always having all three types of 22 ammo on hand and letting them choose what they wanted to shoot. There were many times when they preferred the 22 shorts over the louder Longs and Long Rifle rounds. Then when they are comfortable with the 22 LR, move on to 38 special, then later to 357 mag. It is a good gradual progression.