Getting something made in a machine is cheap and easy. Explain what you want and they go do it. Probably get it done for about £30 if that. Likewise the hardening bit done through a company that specialises in, and the phone books are full of them, is also easy and probably about £20. The one I used can harden front back and sides to different tempers and even apply spot tempers to corners and edges where required. A black art to be sure.

Drilling as a weapon tho, maybe on feathers but on anything larger you probably want to increase that drill bit size to about 300mm. Now that would be fun.