Yes, you need an installation kit to go from Double Din to a Single Din receiver. The install kit should cost about $15 to $30.
You can get a single DIN pocket from any car stereo store or you can go to Subaru and get the OEM 03 Forester flip-up din pocket that's silver and matches the rest of the dash. You'll have to drill some extra holes in the mounting bracket but it looks like it belongs on the car unlike most generic DIN pockets.
you say any, but only Metra is actively advertising one for it actually fitting... thats what i was worried about... how much does the forrester thingy cost? (and i'll probably paint it black like Ayrton did)
If you're going to get a black one, every year of RS has a single din pocket with a flip-top door. The 03 Forester one is just the same color silver as the interior, dont know why you'd drop $30 on it just to repaint it when you can get the RS door for much cheaper. Really, any of them should fit. Its a generic DIN pocket, its going to be covered with mounting holes along the side so that it'll bolt into any possible OEM stereo bracket.
go to a circuit city then. guess they don't need your money. i bought mine at the best buys @ north lake mall.
yeah, well, they didn't display them or advertise ever selling them, so i didn't figure it was worth such effort. they dont carry them at Bestbuy either.