National is the house brand of Richardson Electronics, one of today's major tube suppliers. Looking from your left to right, you can follow the name's progression from Varian's ownership, through an outfit named Industrial Tube Specialists. Based on the logo, it appears the last two boxes are under Richardson's ownership of the name.
The tube writing color is blue on the Varian and ITS tubes and red on the other versions. The Varian and ITS tubes use the year-week date format. Some of the red tubes use the same date code and some have no date code. None have an EIA/RETMA manufacturers code.
Another supplier of tubes under the National name was Matusushita. They were totally unrelated to the lineage shown above. National was a brand name they used before Panasonic, but primarily outside the US. Inside the US, they used their Matsushita corporate name because there were too many National brands. Although Panasonic has become their all-encompassing brand name for virtually everything, I don't believe they marketed any tubes under the Panasonic name. The logo shown on the tube box came into being around 1973, so that gives an approximate date for their National tube brand. Sometimes the tube in the National box was branded Matsushita. Tube writing was usually either white or blue.
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