I'll take a different approach here. . .
If you decide to go with an aftermarket setup, usually what you need to do is find seats that will fit in the car properly, the shop you decide to buy from will most-likely have the seat sliders and proper bracket that will connect your seat to your car.
I've been modding Hondas for a couple years, and have 2 different aftermarket seats myself.
(that's Sparco's site)
and then check out Corbeau seats. Cobras are nice, VERY PRICEY, usually in leather. Momo makes great seats, and of course Recaros are the shiznit!
Since you are in Cali, www.showstoppersusa.com
would be a good place to call. They mainly carry parts and aftermarket supplies for Hondas/Acuras. But will definitely be able to direct you to a good shop that deals with Scoobies.
Or, check out Ebay! Just make sure you use the 98.5% rule (don't buy anything from a seller with less feedback percentage than that).
Just checked Showstoppers site. They have a Subaru section. Not necessarily for the Forester, but it sounds like there is a lot of swap options with the WRX, STi, and Forester (as far as seats go).