Googling around I think that the part you found (W0133-1831358) is for the legacy, but not the outback. I'm pretty sure the rear is different between the two.
The part # came up in an older legacygt post. Not sure if a conclusion was ever reached.
After discovering the current expense and hassle to import this kit, I'm going to put this on the back burner. I'll keep my eye open, but it's not worth the hassle/cost right now.