Welcome to the companion forum, I also have a 4 tuning cans, and the only thing I can advise you on this topic is in Madrid.
I wear out the tower is the largest scratch in Europe and it has many four cans, in terms of the replacement that you ask for, the distribution chain is the same as the one that carries the Twingo, R-5, Supercinco, 9,11, Express 1.1, 1.2 and 1.4, you will not have many problems in this regard when finding it, since these cars are not so old, (the Twingo was manufactured until 98).
Greetings and get into the Google, Bichea about the scrapping because the issue of optics and pilots, if not scrapping, will ask you for a kidney.
All the best