Wrecker's or eBay is the practical solution for the motor (get the whole clock).

Read this, for info., if nothing else:http://business.baylor.edu/Richard_Easley/autofaqs/clock.htm

If DIY isn't your thing, try here:http://www.benz-store.com/clock_repairs.html

Good luck

__________________
The Golden Rule

1984 300SD (bought new, sold it in 1988, bought it back 13 yrs. later)