I saw this at my local shop today, is in nice condition. This is the only photo I was able to get. The caseback has no writing except Longines near the upper lugs. I suspect it's 33 or 34mm. Might be too small for me though, the minimum I seem to tolerate is 35.
Likely a cal. 280 with an American-made gold-filled case. See example below for reference. A high-quality movement but likely too small for your taste.