Welcome James. As far as buying a kit, its alot easier to piece together a kit. Are you going to be doing the work yourself or taking it to a shop? I use to own a turbo IS as well but it ended up getting totaled. Now i plan on boosting my SC. I was going to do a 1j swap but im going to do another NA-t Set up. 300-350 is a good amount of hp but you will get bored fast trust me. When i first started thats all i wanted and then ended up around 400 until the car was totaled lol. There's alot of build threads on the forums already just do some research. Good luck and if you have any questions feel free to shot me a pm. Also where are you located in NJ?