Not sure if
this will help, but might be worth a shot. It's a seller from Gemany selling the struts. I would contact the seller and see if they can send them internationally. I know that A8 Parts send parts to all over the world, so give them a call too. However, I agree, you should be ok replacing just one strut. Also I would maybe call around a few other Euro car specialists, just to get an idea of pricing and to see if any of them have dealt with A8's before.