~~~This thread is two and half years old, if that bothers you. But since no one ever offered a practical answer...

Try these folks: Bicycle Bolts, for small quantities of metric security Torx fasteners.

Note: Security Torx is not proprietary or controlled, and anyone can go to a good hardware store and buy a set of security Torx keys. If you park your bike with expensive components in the same high-theft location everyday, security Torx might not be the way to go. As a practical matter, though, if you park you bike with expensive components in the same high-theft location everyday, the thief will probably just take an angle grinder to your u-lock. The chance of a random bike thief just happening to have a set of security Torx keys is only sightly greater than the thief having a Dewar flask of liquid nitrogen and a stick of thermite.