Buy 12ax7 tube

Hi..i found this tube for 20$

I want to know is it original?

https://drive.google.com/file/d/1GDYl5h2hOR3SwxyiBlEIMcDKVqerONH_/view?usp=drivesdk

https://drive.google.com/file/d/1-zm3EtQpsraJdpqIOm5Wic2_-gVlC4nB/view?usp=drivesdk

I also found some jg 5751,trigon,zaeux And cei that i like to know what are they

All of them arround 20$

What about this one?!
https://drive.google.com/file/d/1Y_ZxGf1tJqSGpikc3ym3JhLfUob389u-/view?usp=drivesdk

*zaerix cv492(not zaeux)

What is this?!
https://drive.google.com/file/d/1SxRg18P1ipUnBRWOjlHb0pC-gC1aVMfG/view?usp=drivesdk  

Another vote for Telefunkens. Years ago I found them too bright, preferred Amperex, Mullard, RCA. But I came across a number of Dynaco and Fisher units, too trashed to rebuild, but the tubes were okay. Telefunkens. I have about 40. My preamp takes 4 x 12AX7 and 4 x 12AU7. The Telefunkens are 40, maybe 50 years old, with countless hours on them — but they're dead-silent, tonally rich and true, ravishing midrange, and I hear no brightness: maybe age mellowed them.

The 12AU7s are NOS Tung-Sols or NOS JAN GE's — they're the weak partners in the team. Man was I surprised. Maybe they need burn-in, I hope so.

Sorry I can't comment on new production; I haven't needed them. But I will, so I follow these discussions closely. Thanks all, for the informed opinions.