You can do Rubicon Express Mono Tubes which are now "white boxed" 5100s. The issue is, the only ones that are available for the specific height you need, can not be broken out of the RE BB kit. So you would have to go to 2-3 shocks. RXJ703/04.
If you went to 3" springs then these would work for you. Otherwise the 5100s you need are two weeks out, as you already know!