There were many small glass factories in Germany. Driburg Kristall is apparently one of them. Unfortunately documentation of 20th century German glass in general is extremely sparse and limited to a few well-known company or designers.
I could find that there has been glas manufacture in Driburg from 1750 onwards. Currently a big automated Walther glassworks in Driburg is the most famous. This one seems to be smaller, but may have been taken over by Walther in the past (pure speculation, maybe someone can confirm or deny).
The style of the design is certainly in line with its most likely period, the 1960s/1970s. There were a lot of designers active at that time, sometimes freelance for several companies.