The Crossfire suspension is Mercedes, as is almost all of the mechanical's in the car. I'm very surprised they are saying the OEM bolts are junk. You can get the Mercedes eccentric alignment bolts from a Mercedes dealer. But they will likely ask for a VIN number from an SLK320. Some members have just picked a VIN from a car listing on the internet.

The part number for one bolt is: 2023300118. The part number for two bolts is: 2023300118OE. Depending on the alignment requirements two fit on each side.

I have a 2007 as well and it had some alignment issues. The first national chain that looked at it could not do anything with the rear camber because it is not adjustable as the car comes from the factory. They recommended taking it to the dealer. I bought a rear camber and toe kit made by KMAC and installed the camber bolts/bushings. The KMAC kit is very expensive $380.00, but it worked well. There are other options with adjustable arms. I also needed the Mercedes eccentric bolts for the front.

autohausaz.com sells them:

http://www.autohausaz.com/search/pro...ber=2023300118
If you use ebay do a search on the part number above. I did a search this morning and there are many listings.

http://www.ebay.com/sch/i.html?_sop=...3300118&_rdc=1