More to the point curved end bracelets, I have just realised watch bracelet manufacturers who sell curved end bracelets do it wrong. I could own a 36mm watch and you may own a 50mm watch. Though both are circular and wear a 20mm strap. The curved end might not fit.
A possible solid would be the watch company’s include/offer curved end links for their products.
Who sells bracelets by lug to lug dimensions? First time I’ve ever heard that.