I've tried ordering this from a MB dealer, and no dice. MBUSA won't bring them in, and won't bring in the halon extinguisher.
You're better off getting a Halon substitute and a stainless-steel bracket mounted to either the seat-pan or the center-console.
On our 1988 wagon it's in the center-console (I don't have the storage compartment), the 500E's is in the trunk.
I'll try and post a picture later.
BTW- Dean's roll-bar and extinguisher is needed for the Silver State Classic at his speed-class. Mine only needed the extinguisher.
1988 360TE AMG