There is no set parts list, because everyone has different objectives and goals.
VERY Generally speaking, you would like want a sound board of some type, battery to power it, speaker, either an in-hilt LED setup or Neopixel connector if you go th Neopixel route, one (maybe two) switches, a chassis to hold that all together and a hilt to cram that into. I’d work on designing a hilt first, then the chassis design to see if it’ll be practical, and then you can go from there. TCSS also has a forum, and FJK (one of their moderators) use to do a lot of MHS hilts over the years. He occasionally pops in here, once in a while.