I have a '98 Impreza Outback sport and I really like the body style of it...except the fact that it's a wagon. Did Subaru import the STIs from that gen into the states? I can only find them in the UK. I'd really like to get one if possible. I guess if not I could snag an RS and do a swap if worst comes to worst.

Subaru only started importing the US market STI in 2003 as a 2004 model. If you're going to get an RS for a parts/engine swap, go for a 2000.

Subaru only started importing the US market STI in 2003 as a 2004 model. If you're going to get an RS for a parts/engine swap, go for a 2000.

How difficult would a swap be on an RS. I know in my '98 the engine bay is pretty tight so I would imagine it's not any different on the RS, considering it's the same thing less the hatch. Also, is the drive-train on the STI any different. Or to put it another way, is there anything I'd need to swap in the RS for it to be able to handle the extra power. And finally, what is the engine code for that year STI (unless there's a better choice)?

There are significant differences between the RS, WRX and STi engine bays, you would have to swap out the entire transmission if you were to put in an STi engine. You would also have to swap out the front member as the RS one is slightly different and doesn't accomodate the additional exhaust routing.

Level of difficulty for the mechanical parts swap isn't high, the real difficulty is the ECU and other electrical parts changes required, including new wiring harnesses.

To save you any more questions, here is a link to the FAQ where all the swap info has already been shared:
http://www.automotiveforums.com/vbulletin/showthread.php?t=176338

I have a '98 Impreza Outback sport and I really like the body style of it...except the fact that it's a wagon. Did Subaru import the STIs from that gen into the states? I can only find them in the UK. I'd really like to get one if possible. I guess if not I could snag an RS and do a swap if worst comes to worst.
If your goal is to swap, you can use any base-model L and save money (RSs are still holing their value well), or for that matter, virtually any Subaru chassis that had an EJ motor.

It has become quite ecomonical to find a clean chassis here in the states, and find and importer/swap shop to get you a JDM clip and install all the parts to "recontsruct" a WRX or STi for you here. Several are offering swaps using newer ('02+) USDM motors that will also meet emissions requirements, if that's an issue for you.

Your OBS would make quite the sleeper with an STi motor installed! ;)