[Heuer 2915a] How to identify an authentic 2915a stopwatch

Hi Heuer experts!

I've been trying to gather some information on identifying an authentic 2915a stopwatch, but there is very little info out there seems like.

The reference manual for the Heuer 2915a looks different than the example of pictures I could find, which also differ between themselves slightly.

From the reference manual:
- No "Made in Switzerland" indication on the dial
- Minutes and hours hands are diamond-shaped
- Seconds hand is leaf-shaped


From the actual pictures of the stopwatch:
- Minutes and hours hands are a thin line, not a diamond. Sometimes the seconds hand is not leaf shaped.
- Sometimes the "Made in Switzerland" appears, sometimes no
- Sometimes the serial number is engraved on the movement, sometimes no. Eg. this listing doesn't have the serial number engraved on the movement, just on the back of the case, but everything else looks legit.
https://www.ebay.com/itm/CRONOMETRO...e=STRK:MEBIDX:IT&_trksid=p2055119.m1438.l2649

So for an authentic Heuer 2915a:
- What should the hands look like?
- Should there be a serial number engraved on the movement, or just the back of the case?
- Should there be a "Made in Switzerland" at the bottom of the dial?
- Are there other authenticity indicators?

Thanks!

Sources:
- http://www.onthedash.com/Guide/_Stopwatches/e.12-Hour_Stopwatches/Reference_2915/Reference_2915-A/
- http://www.onthedash.com/docs/Glenn.html