There are not many parts of an aircraft that need plating, but the baggage compartment lock is one example. Mine had significant surface rust and so needed restoration.
After cleaning with a soft wire brush and some adjustment to the mechanism it worked well, but looked pretty bad. Friends recommended that I send it to "Paul's Chrome Plating" and have it professionally cleaned and plated. The results we very good. I chose nickel plating rather than chrome. The less bright finish seemed appropriate.
What is different about Paul's Chrome Plating is that they pursue this rather ancient technology in a very modern way. Once you send them the parts you wish to have plated, they inspect them, photograph them and then send you some website credentials. As the parts make their way through restoration, cleaning, copper plating, nickel plating etc, you can log into the website and view pictures taken during each step in the process. They take very good care of your precious components and you can watch and comment on the work.
The website can be found at: http://www.paulschrome.com/