As you no doubt already know - but I'm state it clearly anyway, the movement of that watch is a caliber "9L" (as indicated on the movement). A nice quality movement!
The movement is also marked "LXW", on the balance cock. This is a US import code used for Longines at the time, telling us it was intended for the US market. The case also makes this clear (Cased and Timed in U.S.A.).
The movement is marked "unadjusted", which means that the movement was not declared to have been tested and adjusted for precision in multiple physical orientations at the factory. This was to cut down on import fees (the US cared about that stuff). But the case suggests the watch was adjusted to some degree after entering the US.
The movement would have been shipped out alone and supplied with a case upon entering the USA (again, as declared on the case).
Click to expand...