About the mx mudguards , i did motocross for a good 4 years and if you want cheap plastics check out the classifieds in 'trials and motocross news' it comes out every thursday, your bound to find something in there !! GOOD LUCK
PS : and at the right price.
Ive got a kheo flyer which is brilliant for kite boarding as well as mountain boarding . i paid 290 for it brand new. it is also powered by a bullet 4.5, its a perfect combination Sci]