[Eliot Ness]

For tubes I like FindAtube.com.  Bob Dobush is a good guy with good prices, although I usually try to order at least 6 to make shipping more reasonable.  eBay has some 6A7's also.

I've repaired tubes like yours before.  Solder a wire onto the stub, then use a solder sucker or wick to get the solder off the top of the tube cap to expose the hole.  Glue (super glue works well) the tube cap on with the wire sticking out of the hole.  When the glue is dry quickly fill the top of the tube cap with solder.  Be quick or you'll undo the wire that is soldered to the stub.  Try it, you've got nothing to loose and might get a good tube again.  Good luck....