Yes, the rear sway bars are the same, front, no. Also look into getting end links, and mounts depending on your budget, it is an awesome, worthwhile mod. I personally scored a Perrin adj. w/endlinks and mounts for my 05 rs from a gent who upgraded from a wrx to an sti. It is a much more responsiv car now.
Linkys for parts!!
www.allsubaru.com
www.boxer4racing.com
www.kastleskorner.com
www.subaruwrxparts.com