Well, there's not really a lot to go on. The fact that the Landeron movement is unprotected makes me think it is probably from the 1940s or early 50s. Honestly, it's a bit hard to tell if the watch is all original without better photos.
Thanks Dan. Photos are from seller. I bought it because I liked the look. Have searched the web for other Leonidas with similar case design but can't find any. Made me wonder if this was a re-case as some point. Just wondering if some Leonidas enthusiast would have some insight. Have several vintage mechanicals and buy what appeals to me without strict regard to provenance. Thanks for confirming the movement as Landeron and appreciate your reply! Cheers.
I have a similar Leonidas with unmarked Landeron movement. These were among the Chronograph Swiss mass produced era where makers were just throwing cases and dials on movements. This is well before the Heuer relationship. This is prior to going off to the watchmaker for a refresh and new crystal.