I respectfully disagree. The fronts fenders and everything between the fenders is interchangeable between all W123 models, though there may be variations of some parts from year to year. The lower outside glass seal is a generic seal that is cut to fit for more than one model.

As for the windshield, it is not like you can't even get one. They are still available new, though probably higher than a sedan windshield. Just check out www.safelite.com for one source (and I'm sure the MB dealer can get one too).