Here is link to Richard Corbin.

He is much more highly regarded than his brother Dave who is CorbinBullets.

http://www.rceco.com/

There is also a forum on AccurateReloading called Bullet Making.

The cost to make 458s and similar is not much different to 270s. I think this is one reason that so many of the custom bullet makers start with the big bores because they can get a lot more dollars per bullet but material cost is about the same.

Richard will make any shape you want.

Mike