Years back I worked at a company that used a Chinese vendor make some pot-metal, flat, "fake-cloisonne" badges (plastic filled, not melted glass) These turned out OK, vendor worked from vector files with notes and PMS colors called out. They could do a "short run" but the cost was high since everything is in the set-up, not materials. These outfits were mainly makers of pins, probably some are still in business.Might not be ideal for this final "curved" product but you could try that angle.