No there are actually some NOS Telefunken/Mullards left over...they're just very expensive and scarce as hens teeth. There are also decent pulls left. Tubes that weren't overused (12ax7's can last and sound really good for a long time as long as they don't go microphonic). I've found old RCA's/Tele's/Mullards in old tube equipment in thrift shops. Mullards sound great in Marshall type amps. I don't think that Groove tube tries to hide where they get their tubes from. It's pretty obvious from their tube codes...12ax7r/c etc. What they do is screen out the ones with missmatched triodes/microphonic/low gain etc. There are still 5 factories that make tubes in the world. They all make 12ax7's and they all sound different. I've tried them all in various amps. IMHO, the Tungsols, which are made, I think, by the same place that makes sovteks, work the best in most amps. Sovtek 12ax7's sound kind of crappy in my amps, but they work pretty well in the amps Fender is currently building.