Check out this thread where the OP custom ordered such board from a seller on etsy.
Folding Chess Board

@zagryn yes, I previously contacted that person on Etsy without luck. They aren't making it any more.

I recently ordered a nice custom box from Zach at PithStudio on Etsy. The box came out very well. He made the board in this thread: https://www.chess.com/forum/view/chess-equipment/new-custom-board-maple-purple-heart-foldable. Contact Zach. He might be able to help you.

That's unfortunate. I was eye'ing one too. Another possibility is folding chess board from Abigail or Nexus. They seem to be the same product but sold under different brands. The board has 60mm squares, just like the original Dubrovnik 1950. Design is slightly different of course.
Here's an old review: https://www.chess.com/forum/view/chess-equipment/review-abigail-21quot-chess-set
Good day.
I've been trying to find a folding chessboard similar to this. Perhaps my google skills are failing. Any suggestions?