The iCarte attachment is available nationwide from KT outlets and from Apple stores and a range of other retailers for a one-off fee of 69, 300 won (US$58.74).
To set a heel would cost from 3000 won (around 15 yuan) to 5000 (25 yuan). To change the entire heel would cost you 10,000 won (50 yuan), which was a pretty fair price.