The tool nose radii shown in this online catalog are those in common use for a given tool size and style.  However, there is generally no additional charge for special radii, if you order at least 10 pieces of a given insert with that radius.  This can be extremely helpful in maximizing tool life and achieving fine surface finishes.  For example, a part which has a maximum radius of .030 would generally require use of a 1/64" radius (.015") insert, since that is all that is generally available.  Using a .028 radius insert increases tool life and improves surface finish, or allows higher feed rates at a given surface finish.  We commonly produce .002" and .005" radii for customers who require tools of this type, as well as .060" and .080" radii to maximize tool life and achieve extremely fine surface finishes in other applications.  Let us know the details of your application, we will make every effort to provide a tool designed to optimize your machining operations for that job.