A Marathon MIL-Spec Stopwatch from the Cold War

I know I'm stretching the Cold War linkage with what I consider a cool stopwatch from eBay, but I do enjoy looking for a good deal on neat military gear.  Once and a while I find something awesome on eBay, but sometimes I get euchred.  I haven't figured out which way this deal has gone, yet.

The back of the case is stamped:

STOPWATCH
MIL S 14823
6645 00 126 0286
GALLET CO
DLA 400 90 C 5008
891707256
U.S.

Meaning:

It's a stopwatch (that seemed obvious)
It conforms to a revision of the military standard for stopwatches
It has a National Stock Number (NSN)
Manufacturer name
Government contract this was made under
Serial number

• Because MIL-S-14823 came before MIL-S-14823A, I going to make the leap that the watch was designed to the specification that was the standard for stopwatches between 1968 and 1988.  It is possible that this watch was made in 1989, before watches conforming to the new standard were being built.  From posts online from military pilots issued similar stopwatches in the mid 1980s, they mention a fibreglass backing.  This stopwatch has a metal case, brass perhaps.  I'm not sure if this indicates an earlier or later model, but the specification doesn't mention anything about a fiberglass vs metal back.
• The National Stock Number is an excellent source of information, but I haven't been able to figure out when Marathon / Gallet was issuing these stopwatches.  Tag Heuer also sold watches conforming to that spec with the same NSN to the US Military (presumably under a different contract).
• Gallet & Co. is one of the oldest Swiss watch manufacturers in the world, and well known to make an excellent timepiece.  I'm unclear of their relationship with Marathon Watch Co., but Marathon may be a subsidiary or related in some other way as they seem to source some of their watches or parts from Gallet.
• DLA400-90-C-5008 is the government contract number this was produced under, which was awarded to Marathon Watch Company, Ltd of Canada, but I'm not sure when the contract was issued or completed. (I tried finding reference to the original contract on American government web sites, but none went back that far)
• The serial number may have additional information encoded in it (is it actually from 1989?  89XXXXXXX) but I dont know enough about their watches to be able to say.

Below is the PDF version of the superseding military specification, which is probably pretty close to the one this stopwatch was made to conform to.