When I worked for a restoration company down here in VA, we used exclusively Frankford Plating out of Philly. Their work was top notch. I googled them and are still in business. You might check with them (215-288-4518) and see what they say. Don't know if John Barger still runs it, but you might ask. If so tell him Don from Bob and Peg's Vintage Tin sent you to them.