Where can I get one of these...

.....or a pair if necessary, posted to France please?
I researched the forum extensively and also printed off the full article re air suspension on TD5 having had a problem with the rear end dipped on one side, even when the ACE is activated fully.
However, a new French neighbour/mechanic I met recently came round this evening with a can of spray to detect air and hydraulic leaks....thinking it may be a slow leak in an air bag. After spraying everywhere and finding no leaks, he/we came a cross a broken bottom bush on the height ride sensor arm which I obviously need to repair asap.
Another associated problem/dilemma I have is, I changed two rear tyres recently as the malfunctioning HRS system (I presume) had scrubbed out inner tread on one tyre, but it now looks like the new heavy-tread all terrain/road tyres (according to my new found mechanic/friend) are 2cms dia bigger than the front tyres and this is a big no no on permenant 4WD vehicles as the rear end is going slower than the front end.
I do have half a brain but am not fully au fait with all the technical and mechanical explanations but any info and help very gratefully recieved.
Riggy.

don't know the answer to the part conundrum (but worth trying paddocks or craddocks) but in terms of your tyres I think the tiny difference wont do much harm if it is for a short time but would look to change the front boots very soon..