Fairly expensive though great quality weaponlights:
https://www.elzetta.com/I have an Alpha (1-cell) with standard bezel, standard lens, and rotary tailcap. My thinking is to have a flashlight with momentary only contact switch rather than a push button switch. Illumination should be momentary only. A pushbutton tailcap runs the risk of constant on which only serves to telegraph your location for a bad guy and provides them with a point of aim.
Nice thing with Elzetta is the use of fully potted electronics which are hardened for impact and recoil resistance.
Elzetta also makes a nice ZRX picatinny rail mount for weaponlights.
https://www.elzetta.com/product/zrx/Another source of tactical shotgun accessories is GG&G Tactical
https://www.gggaz.com/tactical-shotgun-accessories.html