Don't HAVE to finish it with anything. Its already fully sealed the way it is.
BUT......
I either hit it with HUT Plastic Polish while its still on the lathe
OR.....
Usually what I do is put two coats of Deft gloss on it.
DON'T........
Try to use Spar Urethane on it, because it sits and sits and sits and never dries.
As far as making strikers out of it, it makes some REALLY good ones. I've made a couple hundred dymondwood strikers. You'll need a smaller head, and especially a smaller shaft than you're used to. The stuff is SUPER dense.
BEWARE of the dymondwood exploding off the lathe on you when you're turning strikers. Its DANGEROUS.
Here's some strikers I finished a couple years ago. Most of them are dymondwood.....so you've got some size references to think about. I've had to re-chuck a lot of dymondwood strikers because the sound is just TOO low when you take it off the first time.
Also, these all have a Deft finish on them.
Parker