I agree that Fastlane would be a good choice for sourcing out the parts, it helps out the site.

The wipers, I'm not sure on the numbers, but I'm sure lots of later ML owners are aware of this:
Starting in I believe either Feb 99 or Feb 2000, MB changed from a blade with a replaceable insert to a "1 piece" design for which replacement isn't possible. Have to replace the whole blade, although the price it seems to me seemed reasonable. One could also replace the blade assembly with the earlier style, which at that time was still available, although it costs more, was somewhat cheaper to obtain the insert.

Later they also used the same style on the smaller rear hatch wiper, although the 1 piece design AFAIK was never available as a replacement part, you had to buy the whole assembly with the replaceable wiper and after that you could replace just the insert.
Luckily, the rear wiper blade change to the 1 piece design seemed to have occurred AFTER the intro of the 2000 models, which means the blades were being replaced as part of the "free" maintenance commitment program.
I'm unsure what they're using on the new ones. as of I believe the 2003 models, wiper replacements are no longer included in the maintenance commitment . I guess MB spotted the money leak.

Gilly