I ordered from Gmarket, paid by credit card and got just over a week. They did send me an email about problem with their mail service the next day but overall I am very happy with it, still using it today
At the time when I got mine, there is not any available in Ebay. You can try search around in ebay but I heard a few members here had bad experience with ebay sellers about the late delivery. I guess most ebay sellers are getting theirs from Gmarket as well therefore their delivery tim also rely on Gmarket.