here are the locations of the orichalums+'s
1st: Complete Atlantica
2nd: Complete 100 Acre Wood
3rd: Find in chest in world that never was, Brink of Despair.
4th: Get all 50 types of materials
5th: Beat Goddess of Fate Cup
6th: Space Paranoids, Central Computer Mesa (chest)
7th: Twilight Town, Sunset Terrace (you must be Sora