[Advice] Omega Seamaster 600 millitary dial

Good day!
I am a complete newbie.
I found a vintage Seamaster 600 with a Military dial from a seller in my country.

Here is the information from the seller:
Year of manufacture 1966 (I don't know how he defined it)
Diameter without crown 33 mm



In my opinion, it looks somehow wrong.
For example:
All Seamaster 600 models (which I have seen on the internet) have a different back cover than here. This back looks more like a Deville or Geneve model.
The model number on the lid is 135.019 TOOL 106, is this a combination of the Seamaster 600 dial and 135.019 case are posible?

This watch attracted me with its black military dial, untouched in my opinion, what can you say about it and the hands?
Unfortunately, the seller has no photos of the caliber.

I need your help to decide whether to buy this watch or look for a better option?
The seller wants $ 500 for them

Thanks!

You have obviously been doing your research....

Dial not military, looks rather a redial to look like a Ranchero