The cones fall apart when mature, so it may be hard to find a supplier. Growing up in Hawaii I saw many Norfolk Island Pines but can't recall ever seeing a cone intact on the ground. I have seen a lot of beautiful turned bowls.
If you know anyone near a gulf beach in central to south Florida, they may be able to help. There is a bowl blank supplier in Bradenton who may be able to score some for you. He has NIP blanks. http://www.woodturningblanks4u.com/about-us.html