Though that would be rather better if we could restore just a part of a person from backup, rather than generating a clone and then killing him/her to harvest organs.)
Why is it better? You materialize the duplicate, take the organs, and then dematerialize the remains. What's the problem?
If need be - take the original scan while you, yourself, are under sedation. So, when you materialize the duplicate for harvesting, it is under sedation, and never regains consciousness.