These Kalymian Custom Sabers momentary switches work very well and add a high-end accent to your saber build. They're currently available in brass & copper, with more finish options on the way next year.
To add this to your build, you only need drill a hole that will allow the body of the switch to enter the hole - Ex. a 5/16 bit, though additional filing or sanding may be required.
Specifications:
Switch type - Momentary (open)
Body OD - 8mm
Head OD - 10mm