Place to buy
On Every single guide with a Project Box I put where I think the best place to buy stuff is.
AutoHausAZ.com free >$50 shipping) They have PART NUMBERS here, which makes it easy to compare prices. This is my FAVORITE place to shop.
autopartsway.com this is my other new favorite shop
I ALWAYS do a Google Search of the part number you may find a good place to buy it through there.
RM European I've got a part or two here. Free shipping $65 and up.
Peach Parts They have some options.
http://www.dieselgiant.com/diesel_parts_for_sale.htm Here is my kinda guy, free guides, good parts. Nice. Tell him the DieselBenz guy sent you! :)
http://www.mercedessource.com/ Good guides, but they are expensive and retentive anal about giving you a free guide even with a order of a few hundred dollars worth of stuff ...rarely cheaper than the above two. I'm sorry, I just have something against the people who try to sell DIY guides. I think you will sell more parts if people see a good guide and are confident they can DIY.
https://www.rockauto.com/ The user interface is the main draw, as well as extensive part choice, and price
https://www.fcpeuro.com/ They are located in the Northeast, and offer competitive pricing, as well as having an extensive stock of niche parts, including 722.3 transmission bands and drums.
Classifieds Section People can post their stuff here.
Sold here Is where you can buy the syringe hack or the 3M heat Sound shield.