All 7 seat spec XC90 were fitted with Nivomat suspension and only the 7 seat spec was sold in the UK (some other markets had 5 seat versions).
VIDA will list only the parts applicable to your car so you should get the correct part number, the Nivomat shocks are costly so it's not unheard of that people replace them with standard. You can tell Nivomats as they have a rubber bellow over the rod (type Nivomat into Google images....)
If you want to replace the rear shocks with the correct ones by far the cheapest way of doing that is to purchase this kit :
https://www.ebay.co.uk/itm/325145969...xoC44gQAvD_BwE
I would doubt your "clatter" is the shocks - I would check heat shields, exhaust etc. get under it with a rubber mallet.