For your current Combat Powers, you might wanna increase it a bit mroe and attempt to try killing monsters in South Valencia, it would be easier if you could, as you can obtain Elion's Traces Chests from Chaos Loot Chests in that area. They will give you some random Gift Items including Blue Rose Corolla. The lowest recommended CP in South Valencia is 13500, which is already close to your current Combat Powers.
Also, they have reduced the amount of Blue Rose Corolla from 150 to 50, so it should be easier for you to have it finished. :)