It doesn't seem to me that most 3D printing technologies would be up to creating something like that, which needs to stand up to repeated hammer blows. Leaving aside metal prints, most of them use rather fragile plastics, which also have a tendency to separate along the lamination lines. If you really need custom lasts made, consider CNC carving in rock maple or similarly hard woods.

Andrew Werby
www.computersculpture.com