If you are asking for the lightest headers, you do NOT need them.
If you are worried about weight, drop 5#. Any aftermarket pipe will be lighter than stock. WHY are you focused on a super light exhaust?
You would be looking for a Ti system, and super light = $$$$$. You are clearly a privateer, and you need to concentrate on NOT reinventing the wheel, but just putting together a competitive bike that is cost effective, and plan on crashing. You need a bike as close to stock as you can keep it (= reliability and less $$), so you can focus FIRSDT on track time, than SECOND on learning proper suspension and tire set-up. Even if you are VERY good, if you are competitive, you will be pushing it, so you WILL crash, the question is how often and how badly. If you find some 1-off exhaust, you will be fucked after your first crash.
Balanced selection of parts, good jetting, good suspension set-up, good brakes (properly bled brakes!), good tire selection with the right pressure, etc. --- THESE are the tings that can make you faster, not a bunch of 'super light' parts.
Keep you eye on the prize dude!