For those of us who have a fascination with equipment - either
shopping or window shopping, or that sort of learning that is “Gee,
there’s things like that in the world” - E-bay has a thriving
machine-tool trade. Only a certain portion is jewelry-specific, but
there is everything (and links) from steel rules to Million dollar
machining centers. Start at Industrial Supplies, or search. I got a
7" Speedway lathe for $299 + $50 ship (Chinese, but new), that is
just fine, for the money - that’s an on-going deal, by the way.