This is the only place I can find it.. Its from STAR though.
I have had trouble with my hop up as well. I can not even take it out of the gun. When the gun was assembled the screws holding in the hop up were crossthreaded. I havent been able to take my hope up unit since I bought the weapon. I dont have an answer to where you can find the new hop up chamber. Look for boneyard AW-338's.