Very early Mullard EL84s with O-getters?


I have two coin-based O-getter EL84s, with no holes in the plates. One tube is branded El-Menco and the other is branded Siemens. The El-Menco shows "Gt Britain" and "164-519" in white print. There are no etched production codes visible on either tube.

My limited understanding is that the earliest Mullard EL84s had coin bases and a "1608" designation (pre rX1). There were a few different factory codes, all indicating 1954 as the year of manufacture. At least some of those tubes (F4 factory code), had no holes in the plate.

The coin base would suggest very early production, but the O-getter, as opposed to disc or square, seems inconsistent with that. Thanks for any helpful comments.
bilbar
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Yes Viridian you are right I get those two confused. The one tube I need most is a real pain. Its the 7868 I know that number. The problem is that with a few notable exceptions I think that the counterfiet expensive 1940 -1980 tube replicas I have, sound much better than the new production replicas.
The old production 7868 is approaching EL-34 prices and aren't matched. You may say -"so what?" that isn't critical but in the Sherwoods I own they caution that the 2 tubes in each channel must match. I tried a mixed pair once and watched one tube lit up nicely as it should whereas the other did the crispy critter in less than a second or two.
Fortunately the amp suffered no injury I could find. The good part is that it will operate well enough with two matched pairs but it's tough.
The new production 7868 is too fat for the space that this amp provides.
I can't find any old 7189 readily in matched pairs either for a different amp.
I have quads of EL-84s but not these fancy jobbers and I am unwilling in fact unable to pay out the schnoz . I better sell some of my redundant tubes like 120 + 6SN7s. I need a total of five if I were to keep all the amps and pres I have what a but I really am going to sell this stuff. If I do sell all those amps except one that is a pre with really good tubes in there. That would leave me with still around 100 with 3 or 4 pairs as back ups.
Here is a link to Tube Classics that gives descriptions of the various EL84's, hope this helps.
http://www.tube-classics.de/TC/Tubes/Valvo%20EL84/EL84.htm
Yes, I have explored the Tube Classics webpage. The 1954 Mullard coin base "1608 F4" tube there resembles what I have, but the getter-type is unspecified. Mine have halo getters, which I had always thought came after the squares and discs.