I really like these Nut Bone Blanks from Göldo!
I mainly buy their Bone Blanks, for making new guitar/bass nuts, because they're simply the best.
This particular blank is aimed at S- and T-style guitars, and the thickness is spot on! Minimal sanding is required, in order to snugly fit the blank to the nut slot. This saves time, and makes the nut fit perfectly!
Quality is top notch and the bone is super nice!
Highly recommended.