ds 250 swing arm& a arms

does any one know where i can get a aftermarket swing arm and a-arms for my ds 250and any other preformace parts and also what can i do to keep it from bottoming out on big jumps any help would be nice. im running an 07 ds 250 with full power prefromance clutch kit and 14 tooth front sprocket and have shaved off almost 30 lbs of extra crap off the quad