I don't normally like to direct members away from the forum. But they do need a bit of work to fit as you need to change the wiring as the STI lights have separate main and high beams whereas the WRX has a standard H4 combined high/main beam. There is a chap that sells a idiot kit if you like my favourite type of thing that plugs and plays. I've just tried to have a quick look on Fleebay but no joy.
But link here hope this helps
http://www.scoobynet.com/lighting-and-other-electrical-14/659519-fitting-hid-kit-to-a-bugeye.html