I'm inclined to believe Ivo is completely right -- these pieces, with this finish, were not commercialized. In the 80s, Poles had money, but the shops were empty. People waited in long queues, not knowing what they were waiting for, and purchased whatever product was on offer, needed or not. Everyone had, more or less, exactly the same things in their homes, including the same glass and other trinkets. Only people with connections, or US dollars which could be spent in 'Pewex', had better wares. These Wrześniak pieces were simply unavailable to the Polish masses.
At least, that's how I see it. :usd: