Hi Marcus,
such feature doesn't exist in Moodle and although your proposed feature seems interesting, it involves to dynamically create new sections (topics) in the course and I'm not pretty sure if it's the expected behaviour for the "restore to existing" feature, more if your teaching unit is only two clicks away its final destination.
A personal opinion that can change, of course.
Ciao
Backup and restore
restore data in an existing course
This discussion has been locked so you can no longer reply to it.