You should get around 7 from Sage and Matsuri. 1 from weekend events. 10-8 if you are strong and in a small group rather then the #1 group that needs to share with lots of players. Then you can get them in the ninja questions and survival. On top of that is events such a lucky board that can give out a few more. You could always use your monthly event points to buy them if you don't want the med refines/ thread.