Hi Michael,
the runs, numbering, are never reliable and can be complex. They can change depending on the decade. For the fifties, when translating, often they "are up to" not exactly the number. In the sixties, maybe a 100 were made, as in this instance. I would think more is extremely unlikely, less is more likely, 100 is possible. Only for glassexport orders were numbers exact. Sometimes, the numbers could be exceeded, if something was really popular,the pattern books would not record this. In the book, I mention specific instances where I was lucky enough to be able to ask Jaroslav Svoboda, "when the number says this, how many were actually made?" He kindly replied regarding specific patterns, this is in the book, where he commented specifically. His answers characterise the situation at the factory during the dace he discusses. Your Jelinek piece, I would guess a 100 were made max. A good option would be to email him using googletranslates. He seems to me, a very kind guy and if he remembers this piece and has the time, would happily email you about it I am sure. Anyway Michael, this is not your rarest piece. You have one piece in this thread, that is labelled unikat in the pattern books.....
yours
Robert (bOBA)