WELL DONE Anik.
As everyone says, it is indeed from that range. From memory, I also think that particular shape may be shown in Czechoslovak Glass Review -- considering what it is, it's worth a look if you can get to a library that stocks it. You'll enjoy it. Bear in mind they were distributed in a number of countries, and translated into each country's language. You should find the photograph (also 'from memory') in the special supplement published for the exhibition in 1958.
As Jindrich says, the task is now to find out more about Mr Lebeda - and find out who the main designer was, unless Lebeda also designed the forms, colours and cuts....
When I went to Prague and met the wonderful Jindrich, we also discussed how rare this range actually is. It's clear that I think it's rarer than Jindrich does! He'd know better as he is actually there and sees so much and talks to so many people. However, I still haven't seen more than a very few myself so, at risk of being shouted down, I still class them as 'rare'. Let's see how many turn up over the next few years, but I really do doubt there'll be too many.
I'll also post a picture of a unique cut piece I stumbled across in a random antique shop in Prague. Jindrich has seen it. I think it's a stonker, but I just need to get a professional picture done, as it's not at all easy for a rank amateur like me to capture properly.
Well done again,