From the docs of Storable:

There is a Clone module available on CPAN which implements deep cloning natively, i.e. without freezing to memory and thawing the result.

So I'd recomment Clone or Scalar::Util::Clone. There is also Clone::Any which is an interface for the existing clonecapable modules.

Of course, Storable has the advantage that you can save your structures to disk (including code references).