Found this today. Can't seem to find anything on this particular one I'm familiar with the brand but lost on this piece
Gubelin was, and remains, as you may know, a retailer. As is the case with the watch you have shown, they typically sourced high-quality base movements from other manufacturers, and finished them in-house. This is an Eterna movement, though I am not sure of the caliber. Judged by the funky case design, the watch was likely manufactured in the late '60s or early '70s.