Great work Floor, you made my day with the sample card which shows the red spherical simulated painted chevron.
It is the first time I see this type on a card and I was really excited.
This bead is in our chevron book as # 488, 497 with a couple of other colors.
These were very rare even in the 70s, probably because they are hollow and fragile so only a few survived years of handling.
If the card is in the Jablonec Museum, there is a good chance that it is Czech.
Do you remember if that bead on the card is hollow?
Is the name on the card the maker, the customer or somebody else?

JP