[Q] Help: EFS folder borked, any way to restore it without backup?

I tried searching for a solution to this in the forum to no avail.

I do however have an EFS backup of my previously stolen phone (Also an S3)
and a thought popped in my head: Can i use that backup and fiddle with some files to show my current IMEI and SN (which are written under my battery)
to turn that old EFS backup to a valid one?

I would appreciate any help and/or kind words to hold my spirits up until tomorrow, when i'll be able to go fix it at the service station...

Thanks:p