26650x1 or 26500x1: smallest body with a "hot" LED assy?

[pnwoutdoors]

Am looking for suggestions for flashlight combinations (head, tail, body, drop-in) that are powered off a 26650x1 or 26500x1 cell, and that support one of the hot drop-in LED assemblies (exceeding 400 lumens). Goal is greatest run time with this 400L single-cell configuration. Can use any factory host, or any of the various custom-milled hosts our various CPF flashaholics produce, whether currently available or not.



Body+head+tail, drop-in LED over 400L, in 26650x1 or 26500x1. Suggestions?