How about searching wikileaks? I just started looking into the Podesta emails and found lots of hits for Manafort.
Glad to help.
Regarding Manafort…here's his assessment of Ukrainian elections back in 2006.
https://wikileaks.org/plusd/cables/06KIEV1157_a.html
If you're looking for a plant to infiltrate a campaign and setup a Russian narrative – he's the guy.