[Wavytone]

Yes I have. I know someone who has had one - and a Unihex - since the 1970's.

That Polarex type never caught on - 3 eyepieces isn't enough, and 0.965" was obsolete even in the 70's.

The Unihex also had one huge advantage - it had a threaded hole to take a very big 60mm Kellner (Unitron) that was ideal for these f/15 refractors. That eyepiece is close to the modern 2" Barrel size and has the mating screw thread cut directly on the barrel.

The 0.965" eyepieces had a very limited field of view due to the small barrels.

The interesting part is that the hexagonal body of your Polarex looks suspiciously the same as the Unihex body, suggesting the Unihex parts were cannibalized to make that.

Possibly collectible, but a Unihex remains a lot more desirable !