I don't think I'll be making it to Victoria any time soon, but I will note a couple of things.

One thing is that gunk tells a story and to some people has value.

Another thing to note is that ultrasonic cleaning in a mild soapy solution can get the scum off the metal parts, leaving what's left of the case hardening intact.

Another thing that's worked for me is wrapping the metal parts in Kroil soaked cloth for a couple of days and wiping them down from there. It leaves some crud in the deep recesses, leaving character while clearing the general haze of years of caked crap.

--Tinker