I've read through the thread, and have seen members mentioning they bought their throttle body from places like carguts.com and ebay. I've used the part number to search myself and found various results from ebay. I'm very new to this sort of thing and don't want to end up ordering the wrong parts. Is buying a used part from someone off ebay the best way to go? I would prefer to buy new but does it really matter? Is all I need the actual throttle body, or should I make sure other parts are included? I did take note of getting a new O-ring from Mercedes for the installation. I plan on finding and buying the part myself and having a shop do the work for me as I don't trust myself to do something like this.

Thanks for the direction!