It seems there aren't quite that many NPB teams interested in Kazuo Matsui. Ages appears to be one of the issues, at least for the Yokohama Bay Stars. And while a reunion with the Seibu Lions might be a nice trip down memory lane, the Lions already have players like Yasuyuki Kataoka, Hiroyuki Nakajima, and Hideto Asamura up the middle. However, it seems the Lions would be willing to consider it should Kaz's return to Japan become a reality.
That all said, it does seem as though the Eagles are interested in Kaz (they already have some guys looking into him). While they do have players like Kensuke Uchimura, Yosuke Takasu, and Naoto Watanabe up the middle, it seems the team isn't completely convinced that they're enough (Takasu and Watanabe are also somewhat injury-prone).
As an added bonus, the Eagles also have Toru Kusuki working in their scouting department, the same scout that was working for the Lions when Kaz was drafted in 1993.
So the Eagles have a need and they have a connection. The one thing they may not have is the money.
Of course, Kaz also has to want to return to Japan first.