Maximum Target Level 85
"This scroll will upgrade the Tier of any Legacy on a Legendary Item of up to Level 75."
This item also comes from the deeds:
Draigoch's Lair -- Tier 2
You can win this item from the Lottery: Lottery of the Devout and/or Lottery of Rhovanion and/or Lottery of Angrenost of which you can enter at http://my.lotro.com/home/lottery.