Thanks for the reply ZERACER, I hurried through writing that post and neglected to say that I've already been to three auto parts stores in the area, as well as Lowe's Home Improvement (hoping to find something in their specialty bins). No luck.
I have started scouring the web looking for a replacement, or something similar to original equipment. I've even tried looking for a parts diagram for this, and was hoping to find a part number. Nothing. Lastly, I tried looking for similar parts on the Mercedes parts sites.
I'm still coming up empty.

If I can't find one just like it, i'll have to resort to an e-clip or a c-clip. Not what I was hoping for, but it is, what it is...