It sounds like a new key and is overpriced. Use the Find feature and type in Torsion Bars. I just did and found a bunch of stuff.
Here is one on a two inch lift:
http://elcova.com/groupee/forums?a=tpc&s=2826088551&f=2606011751&m=373602296 2&r=2576091672#2576091672
Adjustment screws:
http://elcova.com/groupee/forums?a=tpc&s=2826088551&f=6706011751&m=481607256 4&r=2456093884#2456093884
The reason I bring those two up is you will find there MAY be hazards to that kind of "lift". Then again, maybe not.
BTW, I believe I read in one of those threads that a 2500 series key will do the job.