RED DOG

From the looks of the parts catalog, the pulley to which you refer is the "Tensioner, Supercharger Drive Belt". The catalog lists 2 part numbers for it, and they are:

05143092AA
05159903AA

Not sure why the two part numbers, but the stealership might be able to shed some light on that. I did find the first part number for about $80 here:

TENSIONER. Supercharger Drive Belt. for CHRYSLER CROSSFIRE (2005, 2006) (05143092AA)

Don't know if this is the same pulley, but it is listed as the idler pulley for an SLK 32 and ~looks~ similar:

http://www.autohausaz.com/search/pro...0Pulley/Roller

There might be other places that have it as well - best I could do on short notice. As far as getting a replacement bearing, you might just have to pull it and take it to a local bearing house to see if they have a match for it.

Good luck!

RL