[codefox1]

I'd vote for an octal socket as a replacement, and of course you can use the base of a dud tube for the plug, or better yet an octal plug with a snap on retaining cup. That is if you don't mind making a change to your set. I've seen many many 4,5,6,7,9,10,11 and Octal speaker connectors, and as stated, some of these are not the same configuration at corresponding tubes. Old Organs, PA amps, and many radios had really strange unobtanium plugs and sockets, and the rerer they are, the more likely they will be hopelessly broken or missing.

In any case, many have a shoebox or two of these odd plugs and sockets, so a picture of exactly what you have and want to do with dimensions might drum up a contribution. Use the Wanted forum here if you wish to.