Different Show Jumping Bit?

I ride right now in a three-ring elevator bit that has a jointed mouth piece. It isnt legal for my equestrian team and my coach thinks that i shouldnt use it for anything other than cross country. I need it because my horse pulls when she really gets into jumps and sometimes will run through the bit it is not because of rider innability. I am going to be competing in barrels and 3 foot jumpers (both english, rockin.) What are any other bit suggestions? I cannot use gags. Any bit/martingale combos would be great too.