Due to the time that has elapsed since purchasing the cut it would have to be good will if the importer were repair/replacement. I sympathise with the position you are in, however it's like purchasing any type of good the warranty period started from the date of invoice, and I must say a 12 month warranty on a 1/2 cut is fantastic. Most places only offer a 30 day/start-up.
All I can say is be extremely nice to the place you purchased it from, you'll have more luck being reasonable rather than trying to play hard ball as they seem to have fulfilled they obligation under the fair trading legislation.