First, FYI... describing a car like that as rare absolutely rubs some of us the wrong way, because we see it applied all the time to cars that oftentimes aren't really that rare.
Also, we're pretty familiar with this car
... this is primarily an MB diesel forum, after all.
As for what it's worth, I think we'd need to see pictures. Valuing something from just words is very difficult.
Sorry if I come across as unwelcoming -- I'm happy you're here! It's always nice to have more members on the forum. However, your post looks like the annoying kind of ad that a lot of us have seen over and over again ("rare", random facts about car in general, like speed or fuel economy, no pics). It does sound nice, though! Service history is one of the best things on these old cars.