Nobody is doing them atm, due to patent infringement threats. Basically, the guys who offered this service received threats to stop all production by the patent holders of the new pneu kits being released.
There is a thread around here about a DIY frame from G Force that is going to be released soon. I suggest getting one of those since it will be a direct replacement for a Mag frame. All you will need is a LPR for it to work properly.