A travel agency in South Korea ticketed my AONE4 ex-ICN on 24 March. I used a credit card against a USA bank. (I live in the USA.)

The process was quite efficient. I emailed the agency my desired, transcribed itinerary, which I had developed w/ the online tool. With a few phone calls and faxes using a very inexpensive calling card, and some emails, it was ticketed. The agency obliged my request to ticket via AA.

The agency in Seoul -- recommended to me by a fellow FT'er -- was very communicative and prompt.
I invite you to PM me if you would like contact info for the agency.

The cost at the time for the AONE4 ex-ICN was 9896700 South Korean Won, all-in, with the then-current exchange rate making it approx $7320US. This included the10% discount that was available at the time.