Looks like I'll need to replace it. Anyone know of a good place where I can pick it up for cheap? Also, is it a DIY job, or does it need to be taken to a shop to get it pressed in/out?

i believe code3 sells one. or you can PM ML500K and he should be able to hook you up!

and i believe it needs to be pressed in

hpashop.com now carries the c3 replacement bearing. 56$ shipped i believe. you will need a press to push out the old bearing and properly push the new bearing in. most shops will do it for just around 20$

I got a source here that sells it for about $10, but shipping will be about $30 for express. If I lived in the states now, i'd probably buy a dozen or so and sell them cheaply.

cheers~

you need a press. Its basically a $20 job at a shop.