I do not recommend buying ANYTHING from BakaPantsu store ( https://marketplace.secondlife.com/stores/172806 ) because I have HIGH suspicion they are directly ripped from game models, imported to Blender/3D program and rigged for Second Life. Ew!
Anyway, as for those hair themselves, I know exactly where they came from. This store here!
http://maps.secondlife.com/secondlife/Morton%20Mains/48/159/1028
https://marketplace.secondlife.com/stores/101160
This place is called Raven's hair store, and all the products are original. You'll find those hairstyles but also a bunch of great other ones. Best part? Most (or all, I think) are tintable! Visit inworld for the styles sold individually. Also you'll find other anime goodies for sale.