Etank,
Having just completed this exact job on my daughter's 190d, I can tell you that the parts run around $60, so that leaves labor of $300. I completed the job in about an hour (with a lift and air tools). It is not a difficult job, but some way to press the new bearing onto the driveshaft is necessary. Bring the car over and I will do the job for $359. Seriously, without knowing your experience, tools and work location resources, it's hard to say that you should or should not do the job.
Good Luck,
Tom