If I may, what factors are being used here to make the determination that the old tubes are "worn out" and that the new tubes are in the same condition after just a few months?
If the new tubes were in fact matched when new, the data provided does indicate that the match has drifted significantly from what would be considered acceptable when new, but there is nothing in the data whatsoever to definitively state that any of the tubes are in fact worn out.
As for the drifting of the match in the new tubes, before condemning those tubes, I would first ensure that the 10 ohm cathode resistors are still accurate with regards to value, well matched between themselves, and that their ground connections all have good integrity. Any problems here will produce false readings of current draw in the tubes they serve -- potentially showing a mismatch, where none actually exists at all. I do not recall any serious complaints of EH tubes drifting wildly after an initial match has been made -- or has this changed?
Dave
Hi Mr. Gillespie!
The 10 ohm resistors have been checked and checked again. They are quality metal film, 1%, and we matched them before we soldered them in. The draw readings follow the tubes when we've moved them to other sockets like Don has suggested. The cold E.H. stays cold, cold enough to grab on and hold, no matter what socket it's in as well as the low draw. Same goes for the one dissipating almost 20 watts. It's as hot as a fire cracker and it too does the same thing no matter which socket it's in. But the voltages are all good and the same across all 4 sockets.
The less than 8 months old E.H.s have drifted like crazy since we bought them, no matter what position we put them in.
As for the old ones being worn out, we only surmise that they are tired based on their relatively low draw, their subjective sonic output and the fact that the silver getter flash? (if that's the right term) is all but gone. And the fact that I know Daddy put them in the receiver almost 40 years ago (we have the original receipt, they are G.E.s) and were changed out when the original rectifier was also changed. This service was the only service the unit ever received until we got a hold of it, as far as we know! I wasn't around at the time so don't know if the selenium rectifier failed or if it was just changed as a matter of good practice.
Still, the old ones as you can see from our measurements are relatively in line with one another, all things considered.
We can only test based on observation and what our little Fluke can show us.
But all the numbers stay the same and follow the tubes. We write down what we measure, move the tubes and then measure again.
The current draw is "better", as in close to one another, with the 40 years old ones than the new E.H.s.
I would think this neophyte logic is sound, wouldn't you agree? Or are we missing something?
And you are right, maybe they (the old ones) aren't worn out because they sound fine. Like I said they just don't have the loudness factor that the new tubes do.
All of this started trying to figure out why the right channel sounds stronger and clearer than the left, and why one of the E.H.s, on the left, was almost cold to the touch. The cold E.H. was originally installed in the left channel. It stays cold though no matter where we put it as I have just explained and the current draw no matter where we put it, substantiates this as being the tube (I would think?).
But after all of this, the left channel still sound different from the right even after moving things around several times, just not as obvious with the old tubes back in the unit.
Thank you for helping!
Phyllis
Thankfully, all our readings in ohms are good! 
