Well, you got options. The best bang/buck route would be to save up a *bit* more. Another 1-200 would give you enough to buy a camshaft, new springs, pushrods (~$350), and get a decent tune or chip (~200-350). You could just do the camshaft without a tune or chip, but you really wouldn't be getting the most of it. Add another 2-300 to that if you need to have someone install the cam for you.
If you've gotta spend it now, and can't get an extra few hundred, or just prefer the simple bolt-on route, then I'd go with an upper intake spacer ($90, easy as hell to install), and an underdrive pulley ($150, bit harder to install, but doable). Given that you have a CAI and exhaust already, that's about the limit of where boltons will take you. At that point I'd probably use the remaining 250 on a chip too. You'd have enough bolt-ons at that point that a decent tune would probably get you an extra 10hp at least. Chip, pulley and intake spacer total would probably net you around 15-25hp, depending on how good the tune is...