there are only three out on the market right now.
AWR:4-2-1 header;eliminates first cat; $500;10-11hp;you will get a CEL but thats an easy fix just do a search
Racing mazda:4-2-1 header;eliminates both cats;$300 (dont quote me on this);10-11hp; its a probe header so it needs to be modified slightly
Travelers: Shorty header;retains first cat;$500 i think;8-10hp;no check engine lights or mods needed.
personally i will purchase the AWR header as soon as i get the cash. ive talked to some people on this forum about them and they are very satisfied with them. you can also lok into getting a high flow down pipe and midpipe if you choose to retain the stock manifold from Wangner motorsports. hope this helps