Omega ref. 2638-4 (?)

Hi all,
I was looking at this was for my next acquisition and I quite liked it - nice and clean dial with roman numerals and sub-second, but there are some uncertainties around it.
First one is that the ref number quoted is 2638-4. The problem is that there is not enough info on these models from the 1940s and it is difficult to make a proper research. The model that I managed to find with this ref number doesn't have the roman numerals, but the arabic.
A similar model on the last photo (although with repainted dial, seems to have the same dial layout) has a different ref number (2374/5).

Another red flag is the seconds markers and the railroad at 6 o'clock - there is a mismatch. I know this indicates a redial, but the omega logo and signature on the dial look pretty legit to me.

Does anyone hold / have seen this model and could advice on the authenticity?

Many thanks!

Redial !
Google is your friend : https://www.google.com/search?clien...B&biw=1440&bih=747&dpr=1#imgrc=-KsGIk1ne3vJlM

https://omegaforums.net/threads/gor...2638-1-cal-332-freshly-serviced-1050€.140569/

Yes, this is also what I saw, but the ref. of this one is 2638-4 which I though may be different (e.g. having roman numerals instead of arabic ones).