Help! Is this Rolex1675 legit?

[Rolex160]

Hello gentlemen,
I bought an preowned 1675 from a dealer but since it comes naked,
I am really poor at telling if it’s authentic or not, and any recommendations for leather strap or the natos? The jubilee of my DJ looks odd on my tiny wrist, although the oyster one does look better. And I feel like this GMT is my last collection, if not, I had to get rid of my old collections. I really enjoyed watch collecting journey, I was plan to keep a DJ, Omega seamaster, Breitling navitimer and my first mechanical watch purchase Tissot le Locle which brought me into the watch world. You guys taught me a lot about the watches, thank you guys and hope many years later I will login again my Rolex forum account to help the new enthusiasts or ask for another new Rolex watch! By now I have to end collecting since I am not a rich person, keep it on guys!