Solid Silver Banana Plugs?

I'd contact Serguei Timachev, Stealth cable designer, and ask him. (Disclosure: I know him. But bias isn't an issue here, is it?) He's at www.interlinkhouse.com, or email at stnemo@starpower.net. He'll give you good information at least, and conceivably even be able to provide what you're asking about. Worth a try.

I think Alpha-Core is selling solid silver spades (coated with Rhodium to inhibit tarnishing). Drop them a line.

try Audioquest. I bought silver lugs from them - dunno where to get those bananas but I have seen them.