Rental compressors should work fine on these, the spring rate isnt as high as some cars. You could always bring the parts to a mechanic shop, shouldn't be more than $50 to assemble new shocks.
6112s are not out yet, few more months.
Bilstein front, rear, and complete sets with GMTrucks discount - http://www.gm-trucks.com/forums/topic/197020-set-of-4-bilstein-5100s-under-350-delivered/