Wow, nice, so much cheaper than other people were making it out to be online. I read one thread where a guy claimed he had to pay something like $1200 in total, and it was for a miniature poodle/terrier mix.
Keep in mind that the price increases for every additional airline you transfer to during your trip. If you fly Korean Air --> China Air --> Delta, then suddenly you'll be paying 600,000 won for your pet ticket.
Book your flight with one carrier, else you'll be paying a hefty stupid-tax
Also, if your pet is over 5~5.5kg, then it has to go in the cargo compartment, which is a far more stressful and (probably) costly process.