Razer Wolverine Ultimate Controller/Cant buy new thumb grips??

How can you sell such an expensive controller then not sell new thumb grips? I am at the point where i would have to buy a new controller just to be able to play with out my fingers rubbing on plastic, or slipping off the controller anytime i need to do a quick sudden movement. I bought this last year ,tax and all for over $150, and i cant even use the controller anymore because they dont sell grips anywhere. The only grips being sold are for xbox 1 controllers and those dont fit on this. Not sure what im supposed to do here.