Jan Chun (most likely free at the beginning of second season, great young striker)
Server Jeparov (amazing, but may cost you around $3 million)
Ko-Yo Han (relatively cheap, only around $2 million)
Choi Tae Wook (no idea what he'd cost you, but great winger)
Yildiray Basturk (he can still play, it's surprising, but second season he deteriorates quite fast)
Javier Chevanton (to have a big name in your team, was free for me beginning of the second season)
Suk (amazing, amazing player. Insane scoring ability, and great talent, he's young and scores well. He was free for me second season at the beginning, amazing bargain)
A few of these (Jan Chun, Ko Yo-Han, Choi Tae-Wook) may or may not be in your game if you didn't load South Korea (always load South Korea, great players there).