Hi Dave,
After having worked in the re-chroming industry for several years, I can give you some pointers. You can usually find a good chrome plating co. in your phone book, BUT ask around before you go ahead. Many chrome shops are geared more to do manufacturing, chairs tables etc. Chances are you should stick with a shop that specializes in automotive. Check with the local car clubs. There are horror storys with vintage and hard to replace parts getting lost. To be economical, chrome plating has to be assembly line type of work so the shop must be well organised to make sure you correct parts end up with your work order. Also there's a lot of polishing and grinding to make sure your sufaces are nice before the bumpers are plated so they have to be very good preppers experienced with bumpers. Check to be sure that your bumpers will be triple plated like originals. Copper, nickle, chrome. Some call that show chrome but where I worked show chrome was double copper, polished between coats, nickle, chrome. Costs about double. It's all labour. Show chrome is expensive and isn't normally nessessary. Quality oem chrome plating is triple plating. Copper for adhesion, Nickle for shine and Chrome is a CLEAR plate that prevents the shiney nickle from tarnishing. Many shops are not capable of the copper plate. And I have seen some manufacturers now skip the Chrome plate over the nickle for environmental reasons. One thing is, I never had an unhappy customer. There's nothing like unwrapping your freshly chromed bumpers. If you have any questions, I'll answer them if I can.