Along with the KL4 Lux 5 head you could take apart a KL4 head and replace the insides. It's been done.
I have a KL4 head with a Badboy 600 and a Lux 1 with a R2H emitter. The beam on the Badboy head is moderately strong, has a long run time and the beam is has a nice white tint to it.
If you open your options up using the mix and match Aleph heads and Aleph drop-in options you could different heads, Sandwiches and emitters. It would take a little work to get the electronics in the Aleph head but it is nothing very hard. A couple of hours work would reward you with an Aleph head and drop-in. Drop in electronics options include Downboy, Nexgen, Madmax, Wiz and Wiz2. A MiniPro and others I can't mention now could also be used.
There really are a lot of options using the modular Surefire/Vital Gear platform.
Below is another variation on the VG1. It is a silly but working at full power VG1, Downboy 917 and Aleph 3 head safely powered by a 3.6V RCR123A cell.