[HKMk23]

Well, there's this rather spendy workhorse that is hand-cranked but can be easily set up with an electric motor to be belt-driven.

Others I've seen are all-manual, like THIS one.

I'm in the market and talking to some friends who've done quite a bit of their own grinding in the past. I'll ping you back 'n' let you know what I learn.

[boxlunch]

Thanks so much!