Revo
ยทI was sure I'd read on this forum (thinking in particular of this thread and the brief strap discussion on @Revo 's entertaining welcome thread here https://omegaforums.net/threads/considering-a-vintage-seamaster.130269/page-3) that it was possible to put a 1m wider strap on a vintage watch if you used curved spring bars. My watch has 18mm lug width, and the smallest Omega offering is 19-20mm.
KP
I aim to amuse!
Have you had a look at the 6B/2617 or any of the other straps here: https://af0210strap.com/
Lots of options @ 18mm