James. Your picture shows LHS and you ask for RHS cv?Either way the cv is the same and seals not.
With the seals be careful, In about 1982 the axle changed from: Oil sealed inside the diff, and the diff lock stuff ran "dry" in the axle tube with assembly grease only. Your picture I think is this version.
They changed it to: Oil sealed into diff and axle tubes ie diff lock also ran in oil and the seal was in the axle tube inside of cv joint.
Latter seals are available and some former not, like the inner rhs seal is not available from any sources as far as i know
In your picture I think 526 is an o-ring, 49 is a seal and i think both might be available.
If you replace any of these seals you need to remove the centre portion of the diff. you know I am sure to note carefully the spacing shims.
Hopefully Peter will chime in here. His is the last word imo.
I can help you with the CV joint you are looking for, with a massive search I managed to find 2 after Mercedes Germany told me that they cannot help, I bought both and thus have one spare.
You can contact me at 084 6188889 if you are interested.