I immediately bought three and with shipping it will cost $67. They say they work perfectly in GZ34 applications but don't know what they really are . The samples shown are dated around 1985/6. I'm willing to try since my current '34's are from China (Ruby, Valve Art, Sino...) and so far I haven't changed the rectifier (Sino).
They are in Ankara Turkey, so $13 shipping doesn't seem too bad. Should take 3-4 weeks to arrive.
Anyone out there know what they may actually be?