solid scape printers are just for this. they are small, and "relatively" cheap (at about 25k). build volume is 150x150x100mm, and runs about $7000 to fill that entire volume, which is quite alot of jewelry. its pretty cost effective on small parts that can be well packed. on large hollow space inneficient parts, its probably not worth the money.
theres nothing in the super cheap hobby territory that i know of that is viable for real work - otherwise id already own it :P