It looks like 180G, silver grey, as show in the photo ablit 3/4 down the page:

Pagoda SL Group Technical Manual :: DataCard / PaintCodes

 

Mercedes have several different silvers .
The paint is listed under 3 digit codes. On your car look at the metal plate on the radiator support panel. There will be a 3 digit number followed by either a "G" (Glasurit) or an "H" (Herbert).
You need to get a copy of the Glasurit Mercedes color chart and work from there.
There are a couple here as an example.
Mercedes-Benz Ponton Paint Codes / Color Charts © www.mbzponton.org
Glasurit

 

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