Not sure about the case back. It looks like 22538 to me, but that reference seems to have been for an Aero-Compax. The case number may have been polished or photoshopped out.
The calibre (287) and the gilt parts of the movement might be helpful in guessing at a date range. I would refer you back to Sala, which I don't have at hand at the moment.
What I don't understand is the weird reference to Yalta. Roosevelt and his Movado were at Yalta. Truman wore a Tri-Compax several months later at Potsdam (but not this reference). I believe he received the watch from Stalin in exchange for Poland. It might have seemed a good deal at the time, but Truman soon realized he had been swindled, and, infuriated, took extreme measures to keep the Russians out of Japan. And the rest is history...
http://omegaforums.net/threads/universal-genève-tri-compax-ref-12551-truman.8103/