.csv upload for bulk user custom field changes

Well, my use case is for restoring some user custom fields which I inadvertently wiped for a bunch of users (see Problem with manipulating custom user fields from the Rails console). I’ve got the backup on a staging site, and I’ve also got them as a .csv

When you say ‘easy’ I’m guessing you mean it would take you a few hours to bash something out that would do the job. Can you give me a cost estimate?