If you don't need the bells and whistles of a fully networked arcade set up for Street Fighter IV and you're willing to settle for a bit of local one-on-one, importer NCSX has you covered. They're soliciting SFIV hardware for pre-order starting today, due to ship at the end of August. It'll only set you back about $US 2590 (with an $US 880 deposit required), which is reasonable enough. More reasonable that $US 23,000 for the whole kit and the kaboodle. Oh, it's completely beyond my personal means, but if you've already got the arcade cabinet up and know how to install a Taito Type X2 PCB, this might be for you.
The full package comes with panel artwork, Street Fighter IV network ID cards and a Versus Communication Kit—you could technically take your fights online—and, of course, the game itself. Let us know if you plan on picking one up.