A nice example of a 1958 gent's watch, both case and movt are marked L8. This is the 11ACAC, an American design which can trace its roots back to the 10BOAC. It was designed and the ebauche manufactured in Switzerland, by Bulova, utilizing their own design, and imported to the US for final finishing/assembly, although some were probably imported complete. The lack of import code is odd, perhaps they were no longer required by 1958?
An interesting case design, I have included an angled pic to show the pattern on the sides. The pics really do not do this one justice, it is a thoroughly nice watch.
I'm thinking Sun Clipper.