Snagged these from a guy at the flea market Saturday, and paid $30 for the pair. I plugged them in, and they sound really nice. They are made in Czechlesovokia so they are pre czech republic. Boxes and tubes appear to be authentic with a little age on the boxes marked E83CC , but the tubes are new unmarked. NOS is my guess, but since i am a tube noob i fugured I couldn't go wrong for $30.