Not the usual Swiss/French/UK or US case, but purportedly made somewhere in South America. I would get the case checked for gold content if I really like the watch.
The watch is not for sale I think. South America is a possibility I have had in mind. Any way to positively identify it as such?
I did some research but found no proof that any SA countries actually have had that style of hallmark - which looks similar to part of a Swiss hallmark. That's why I said "purportedly". Best just to test for gold content.
An Archive Extract would definitely be helpful to determine the origin also, but I'm not sure the cost could be justified for the owner or not.
I think the Archive supposedly keeps record of all movement's serial numbers (except the missing ones).
My bet is the watch was cased in Switzerland in a stainless steel. When it got to the destination, the guts were installed into the locally made gold case. These often are real 18k gold, but not completely solid all the way through. Many times the gold is built up around a brass or bronze ring.
The dial appears to me to be too big for the bezel opening. Something might have been swapped! Dial? Case?
Guessing the case, perhaps having been made locally, might be the culprit? It could also be the angle/crystal, but it does appear a tad tight.