I'm still missing 8 cards to complete my OS16 set, which I've shown below courtesy of GeePeeKay.com
I know about 2 more of these being available from the 2011 Flashback Series 2 set as #70a/b Idol Ira & Ken Tiki, but I'm still waiting to find a good deal on a matching pair to fill-in for #659a/b in my OS16 set.
For the last 6 cards needed to complete my OS16 set, I've discover that 3 of them are available as bonus cards in the 2012 GPK book. I guess I could get 2 books to complete the last 6 cards. I'm not currently aware of any other way to complete the final 6 right now.