Fletch, surely you know all about buying tubes. Is this a troll? You seem to always have a lot of good ones for sale, so assuming this is a rhetorical question(s) for some reason.... (btw, obviously the answer is the latter, above.)
The reason I started this thread, long ago, was I sold some tubes, that were relevant to this. They were Siemens NOS E188CC's. They were new, unused, but were labelled something else. I used pictures and descriptions, but still the buyer initiated a claim, because they were not labelled Siemens. I wanted to see if the A-gon community, felt as I did, or as he did.
Everyone should know that a tube from one manufacturer can be labeled for another brand and this is indeed just a different print on the tube or different box.
All information available online, there is a tube asylum forum for tube nerds, an interesting read if you want to get lost for a half year.
Price for the same tube can be different from different sellers. Those who own a warehouse full of tubes and selling them for 50 years know very well what they are doing. Some of those websites are so old school and not user friendly, but the owners are friendly and available by email for international buyers like me.
I've noticed that ebay prices almost always higher. But some specific tubes are only available on auctions.
Old tubes can be tricky and it's nice to buy only tested/matched tubes with guaranteed full refund/return if anything is wrong on arrival.
The guy who wanted his money back probably didn’t like the tubes in his system and used the label as an excuse to return them. I suppose it should be obvious from the pictures, but you could add to the description Made by Siemens, labelled Valvo or whatever. Even that probably won’t help. There’s another thread just started about buyers lying.