I'm surprised to hear that as Pittsburgh is home to the Pittsburgh Vintage Grand Prix. I would think there would be a vintage car culture there. Have you tried networking with some of the local car clubs?
To offer some recommendations when I restored my Mustang, I used Qual-Krom up in Erie for all my chrome plating work and Bruce Dell over in the Youngstown area for metal polishing and dent removal, he's amazing. I had the same problem in the Canton, Ohio area finding a plater that would do small batch work. What you have to remember is that these commercial platers are in business to make money, ie: volume. I was able to get around that by getting the owner to take an interest in my project, show him my car and what I was trying to accomplish. He agreed to plate my basket full of parts and in return I took him for a drive when the car was complete, we became friends, somewhat.
Hope this helps,
Greg
https://qualkrom.com/
https://www.dellmetalpolishing.com/