This is the exclusive distributor for Team Magic: http://www.wolfhobbies.com/ and you can buy the K-Factory from them.

You can also search for on-line stores in Hong Kong or Taiwan for K-Factory parts.

WARNING!!!!-- some of the K-Factory hop-ups are for the E4 and not the E4RS/FS so be careful if you order. Example is the center brace, it is for the original E4 that goes UNDER the top plate.