Proofed in 1972, which was likely also the production year.
While Borovnik double rifles from this period are not rare, the strong Kersten bolting ("double Greener") of this one is quite uncommon, for a SxS.
I wrote about my Borovnik DR to the makers a couple of years ago and my e-mail remained unanswered as well.

With kind regards,
Jani