So, has anyone found all of them yet?
I've only gotten #1, #2, #3, #7, #8 and #10 so far. I'd use a guide if I could to speed things up.
Edit:
Just found #14, #4 and #5.
Remember that you don't need to complete the quest to save that you collected the memento. You can lose all your health and quit the quest after finding the item.