Sorry Hanz, what is OEM again?
I'm thinking the same thing myself, just wondered whether rolex has a buckle? especially like your Zenith clasp?
OEM is Original Equipment Manufacturer.... i think...
Original lah tu....
There is a clasp that is like the Zenith one but it only works with the Rolex Original Strap.... yeah... i know...
And the clasp is only equipped on brand new leather strapped Daytonas.
You want one? I ask around... Rose gold? Ready to fork out 9000+ including strap...
Solid gold? Almost the same region... and most surprising of all, stainless steel... can't find any....
Pin buckle is 16mm in size and I checked around for straps that taper from 20mm to 16mm and none look nice enough.
If you're still keen, maybe I can get 2 and save on shipping? (cheapskate move)
Or I can PM you the place...
and you have a look...