An Initiate v3 is a solid saber to get for a youngster.
It won't have sound, though. For that, I would recommend the (very new!) Obsidian LITE sabers, which start at $160.
Insofar as options, you have two broad options:
* Get an Express Options saber -- lots of details are chosen for you, and those are worthwhile choices. You just need to pick a blade colour.
* Pick your own options.
If you pick your own:
* pick a color. Up to you.
* pick a blade type: if you get a red colour, I would recommend a Heavy Grade blade; otherwise, get an Ultraedge Heavy Grade blade.
* 32" blade length
* skip all the other options.