I had one of those some 40 years ago, lovely gun.
Have you measured the dovetail width? In an old thread on here someone measured them at 0.620 inch, which equates to 15.75mm. Older CZ/BRNO rifles used a 16mm dovetail, I was wondering if any of them would fit? If this was the case, and you want a more "classic" look, then a set of Recknagel CZ mounts might fit your needs.
https://www.alanrhone.com/images/pro...rts-july16.pdf