I just bought a 2008 Suburban LTZ, 5.3 4x4. My rear shocks are crushed in and the mechanic can't identify the part code off of the existing shocks. Looking up the part on RockAuto yields a ton of results. I narrowed it down to a few OEM parts and wasn't sure which one I need. Attaching pictures of the options. There are many, many more options but this was in the original ride section. Thank you in advance.

 

If you entered your vehicle info into rockauto correctly, then everything you see should fit. They even break it down by quality grade for you.
Get some nice KYB gasajust. You can also look them up on the KYB website.