Engineered Source offers a variety of secondary services for both standard and special fasteners, with additional detail available at http://www.engineeredsource.com/customized-special-fastener-supplier-orange-county-ca-s/108.htm.  Chrome plating is typically done either in barrel form for larger quantities or by individually hanging the fasteners, which is significantly more expensive.  For parts that serve a critical aesthetic function, like screws on musical instruments, individual plating is preferred to limit the imperfections.  Barrel based chrome plating however is typically the ideal scenario for applications where cost and corrosion resistance are relatively more important than the aesthetics of the parts.  These chrome plated 316 stainless steel (easy to distinguish with the stamped dot at the flat head to designate the 316) sheet metal screws were barrel plated at approximately 30,000 pieces.  We stock these parts for our customer on a blanket purchase basis and release as needed throughout the year.