My recently acquired SM300 came with a modern Omega leather strap which is not only too small for my fat wrist but IMO is too narrow for the diver. Whilst I look / save up for a period correct bracelet I was going to put the watch on a NATO. However, a company was advertising their wares on a FB group and showed an SM300 on their sail cloth strap. It looked to match the watch perfectly so I bought one and had it fitted yesterday. The company is Avel & Men, I have no ssociation with them, just love this strap. I searched OF and found no mention of them so thought I'd share in case anyone else can't find the 1,000s for a bracelet right now.
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Sorry - I really don't like that, it makes you focus on the strap and not the watch - I think it would look much better on a cheap plain NATO - but everyone has their own tastes.

 

You are obviously much more fashionable than me, I prefer the traditional.
NATO or vintage Rubber Tropic for me.

 

It causes me to focus on the strap, cool as it may be, rather than the watch which is cool without a doubt

Have fun
-kfw