Though ipil-ipil trees grow in abundance in the Philippines, nobody makes necklaces from it's seeds in this manner anymore. I saw one being sold at Ebay by a Canadian for US$ 24.99. The seller says it's vintage. There are a few also on Etsy ranging from 3 to 8 USD. There were earrings and bags too. They are all vintage and some say that they might have come from Hawaii.
Well, I'm not selling this one. It is treasure. Maybe I'll learn to duplicate it. There's an ipil-ipil tree at a vacant lot here in my neighborhood. ^_^