I've designed a few molds for injection molding processes, but never actually made the parts. Begin with contacting local mold making and plastic injection mol

I've designed a few molds for injection molding processes, but never actually made the parts. Begin with contacting local mold making and plastic injection molding companies and ask if they do small runs. If not, ask if they know anyone who does. Thomasnet (http://www.thomasnet.com/products/plastics-injection-molded-short-run-95924106-1.html http://www.thomasnet.com/products/plastics-injection-molded-...) has a decent directory of these types of manufacturers. Be prepared to give them CAD drawings of your part (or at least engineering drawings), any manufacturing process plans, product requirements, preferred material (specify a type-ABS, HDPE, LDPE, etc), and probably some other things I can't remember. They usually aren't product design firms, they make molds and then use those to make parts. They may be able to help you select which resin to use, but do not depend on it.