Sorry kildrought, had it sorted before i read your post but cheers anyway.
i rang a couple of locksmiths in Tallaght and was quoted between 160-200 euro to fix it,so i called brown bros as mentioned and I got a bloke who talked me through what was wrong,told me how to remove the barrel over the phone and just sold me the part for 35 quid. winner, and to think someone wanted 200 quid for what was a 2 min job. i would recommend brown brothers .
thanks for replies