W210 Estate rusty rear floor pan repair parts A 2106301760 & A2106301860

[stuboy]

My W210 Estate has a "little" rust problem on both sides behind the rear wheels, where the spare wheel sits and the same the other side.

Can one of the guru members confirm that the parts to repair this are:-

A 2106301760 & A2106301860

Can you also suggest where to get them from?
Are they only a main stealer part?
What is the best way to attach them?

Thanks in advance
Stu