Looks to me like we got a new member... lol
www.6gc.net
Just so you know... the OBX headers you won't be able to pick up anyway because they are on back order for years lol.
Aside from that you are looking at SRI and a full custom exhaust.
I hate to break it to you but its not a car that you can just throw stuff on and make it go fast. This isn't a honda civic.
The cheapest means to get more power would be to ship your cams out to webcams and get the 294 regrind... that'll add around 20 peak hp but its a $600 job.
With that said we both know how these cars handle on the twisties so if you're willing to put the work into it you will enjoy it nonetheless.
If you're looking for power your best bet is either a custom turbo job (which will be explained on the site) Or a 3s series engine swap from a Celica GT-4.
I hope you look into us and enjoy your ride.