Let me know whether you ever got that Seismic Toss Chansey. I've been thinking about putting that one together; that and another move (Mud Bomb, only other attacking move) as well. Maybe I can help you at the same time.
I have a Friend Safari, so the HA is also a possibility (Healer I think).
Regular Kyurem is still a better choice, as its slightly higher Special Attack means stronger STAB Blizzards. Kyurem-B's physical movepool is very shallow, as it doesn't have too many physical moves to take advantage of its 170 Attack.