Well, you didn't tell us who is out of stock, but with your lift shackles you could run some 3 inch Downeys for about 4.5 inches of lift.
You could call up a place like alcan or betts or deaver and have a custom set made. If you look in the rig gallery section for bluey the wonderslug, that truck is on 4 inch skyjakers with extended shackles so the skyjackes can be made to work.
