Chances are you may stumble across something 3 phase and Italian, which would likely be a 600mm machine, or possibly 540mm, or even the 450 which Sideways and Deema worked on.
If worried bout big motors, the 540 SNAC machines i.e old green Felders or ACM have 1.5kw motors,
(presumably same deal with single phase ones)
but at the same time if 3 phase, buying the right VFD which has capability of derating motors
can limit yer motor hp to what you like.
I was suggesting more space around the wheels as being less dusty, i.e much like an undersized
impeller, combined with possibly less speedy wheels, look at the other hundred quid Centauro
thread and read the manual regarding wheel speed,
and the slow starting, what's simply adjustable "ramp up" time with 3 phase & VFD might have something to do with things also.
Ps I wouldn't be concerned whatsoever about dust ports or whatnot, you can make'em wherever you like, bolt a bit o plate onto it, and it'll be as good if not better than new.
Tom