There are two Ipsos constituency polls mentioned
in this article:
Jongo seat (Seoul, home of the Blue House and Gyeongbokgung Palace):
Lee Nak-yeon (Democratic) 55.1%
Hwang Kyo-ahn (United Future) 34.5%
Gangnam (affluent district in Seoul):
Thae Yong-ho (UFP, would be first North Korean defector in National Assembly ever) 42.6%
Kim Sung-kon (Democratic) 33.7%
I also found a national poll from them
commissioned by SBS (article is only in Korean), but it only does the PR/List vote:
Future Korea 24
Together Citizen's 20
Justice 14
Open Democrats 12
People's 5