The 04's will fit fine; the offset is 53mm as opposed to 48 for the Forester, but they will still clear the struts. Note that the wheels for the 05+ STi's are no longer compatible with the Forester due the changed lug pattern (5x114.3).
Yeah I knew they had changed them for 05-06, but I had not seen many if any Foresters with the 17" WRX STI wheels on them. I have seen the 18" on the 05-06 Forester and I presume they look the same with the exception of size. I am looking at a set right now, and I thank you for the information. When I get them I will get some pics up.