I see that www.books4cars.com
lists one for $29.95. Just enter your year, make and model and you'll see "86 300E owners manual by Mercedes" listed as one of the options. I bought an engine service manual ($79.95) as well as the CDROM set ($159.95) from these guys. Some time earlier, I bought the CDROM set for my 450SL from MBUSA, and found that books4cars ships more quickly than MBUSA for about the same price. One note, though... I always think when I order a manual that I am going to get a nice new, clearly printed copy, even though its old content. I've found, though, on these old manual (even on CDROM) what you get is very cleary a hastily done photocopy. In the case of my engine manual, it came in a binder with a "slip-in" cover page, and some of the pages were inserted out of order. So if you just want the "content" of the owner manual, use MBUSA or one of these aftermarket guys. If you really want the handsome printed manual, either buy one used or make darn sure in ordering one from MB or books4cars that they're going to send you a real manual and not a blurry photocopy.