Here's what I can do.
If you take a 5a apart, I can have it oxidized silver plated and I will put the patina on it myself for free.
I haven't varnished it because there's no need. It's very hard to take the oxidisation of the silver so it'll keep the look for ever...So your cost would be 40 euro shipping included (and a month waiting to get it silver plated).
If you send me the part put back the screws in the place where they are supposed to be.that way the silverplating will not fillup the screwholes
You have to start with an immaculate 5a, they usually are easy to get apart.
good luck and if anybody needs one too, (maybe unlucky ?) I would be happy to help you...
Bert