You can copy mappings with the Designer:

The Designer provides a Copy Wizard that lets you copy objects in the repository. When you copy a mapping, the Copy Wizard creates a copy of each component in the mapping, if the component does not already exist. If any of the mapping components already exist, the Copy Wizard prompts you to rename, replace, or reuse those components. However, if the object is a shortcut, or if the destination folder already contains a shortcut with the same name, you cannot replace the object. You can only rename or reuse the object. If a mapping contains sources with primary key-foreign key relationships to sources not used in the mapping, the Copy Wizard prompts you to copy the related source.