There are two or three places I would try but I would try only one at a time to make sure I didn't take anyone's time unnecessarily.
I might suggest that the more defined your request is the better but undefined is OK if you're on the fence.
In the Custom/Modified BST Forum you could post a "Wanted to buy: Lux V RB light". If you know you want a MagMod, an SFMod or a FromScratchMod say so. If not then entertain what shows up. This might be less expensive.
If that doesn't return anything that suits your needs let that thread sink and post in the
Homemade and Modified Forum something like "Would someone build a Lux V RB for me?" Again, if you know you want a Mag, SF or Scratch say so.
I would stay away from optics if at all possible. One reason is that they seem to bring out the artifacts in a 5W and also I suspect they may absorb some of the UV rays from an RB. I don't know this I just suspect it.
That EL Blaster VI RB I have? It has a 30mm optic. In an out-of-doors dark environment it still amazes me with how powerful it is. One day I'll install a stippled reflector and 86 the optic.