Well, if you want a .223, there's also the Kel Tec SU 16 which is a neat little rig. You
may be able to find a surplus M1 carbine for your price if you're really lucky, but a Universal carbine is quite likely at that price.
If you want more firepower, the Remington 740, 742, 7400 series of rifles will get you into .270 or .30-06. There are ten round aftermarket mags made for them.
That's about all I can think of at the moment. Somebody else should be around in a while and give you some more input.
BTW, a pistol grip equipped rifle like a FAL or AR type will cost you more money.
Good luck.