hey
well there's quite a few exhaust systems available for our cars... theres the bic divorced dump pipe which is awesome but loud lol.... they do a flanged exhaust from the wastegate pipe to the exhaust so you can vent it back in....
http://www.bicperformance.com, mvp motorsports, aap motorsports and a few others.... we've got a list of supra stores in the FAQ's... check them out
supraforums.com is a good supra site but yes registrations have been closed recently due to trolls bullying the boards
another great one is
http://www.supramania.com
good luck