i have seen 2 pairs, one on rsbb for 200quid and the other on ebay, they were cp5200 4pot ap's but i was too late for them so i cant see a single spare caliper being much if you can get a pair for between 2-300 was offered a pair of ap 6pots for 300 the other day from a lad on ebay but it meant new brackets etc etc so i didnt bother. i have faith in my fellow passion forders