Don't forget the "Ninja Missions and Survival Trial Missions" that gives a lot of Seal Scroll Fragments, I think if im not mistaken, you can get atleast 6 or 8 fragments per day by sweeping the Survival Mission and Breakthrough Trial .. From the Weekend Missions, Scroll of Truth from "Searching for the Scroll of Truth", Seal Scroll Fragments from "Ninja Puzzle", Sealing Package from "Lucky Roll or Dice" .. Redeeming from the Space-Time Strongest Redeem Shop, 5k Exchange Points for a Seal Scroll Fragment .. :D

EDIT : Here, screenshot of prizes from today's Fighting Matsuri Challenge :D