Don't get screwed over by the scum and RMT selling these so high they sell from NPC in Port Jeuno and Upper Jeuno for 120 a pop making a total of 17,280 gil for Scholar Quest. Click on the FFXIclopedia link for details of NPC name.
Just Concuring on what Derian said. You can trade 4 stacks of rolandberries 3 times for 12 sheets fo vellum and it will cost ya 17280. Vellum prices per stack may be less ( and currently are by about 100gil) so go with what's cheapest.
This item -does- sell at the cooking guild in Windurst Waters, but only if previous players have already sold them to the guild. Most likely, this will not happen, however. The only guaranteed vendors that carry it are the NPCs in Port and Upper Jeuno.