First off they have the wrong bolt pattern, so no they won't fit. In addition, I don't see how it would be possible to fit 19x11 wheels in the rear. Also I don't think you would want to run wheels that were so different in width on a Subaru because you'd have to use different tires front and rear.
'04-'07 STi springs and '04 STi struts should work fine.
You may want to look at classifieds on Subaru forums. There are lots of good deals out there, Subarus are very common and wheels can be found easily. Try to stay with 48mm offset and if you don't go larger than 18x8 you shouldn't have fitment issues.