This is where I buy all my stainless steel supercharger bolts by the box:
Bolt Depot - Nuts and Bolts, Screws and Fasteners online
They do not have, or list what you are looking for, but I bet if you contact them, they might be able to get you some from one of their suppliers. They do exist, I have seen them.
"Torx stud" or "Torx headed stud" in what ever M_X pitch your wanting.
~F~