I had a silver 3513 . . Beautiful dial. . . I now have a 3523 with the 1563 850 bracelet which is the same bracelet as on the 3513.
You peaked my interest so I tried it on my 3510 which I believe is closer to (if not the same as) your watch than the 3513:
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As you can see, unfortunately the end-link does not fit properly.
I think the 1471 815 would fit as it is for the sapphire version of the Automatic Reduced case.
And I have seen pictures of the 1563 850 from a Seamaster fitted to the Sapphire Automatic Reduced case.
Otherwise, you could look at the 18mm Uncle Seiko straps for Omega Speedmaster Reduced, but they are a vintage style not the modern you are looking for.
Hope this helps . . .
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