sorry didn't realise my comments would make his followers cry. sorrrrrreeeee.
I have edited all my hurtful comments.
Good luck to Smea the wonderful mortgageless person hurrah
https://www.reddit.com/r/3DS/comments/384vtk/original_replacement_3ds_battery_in_europe/
They do, but do not ship outside the uk. if you want to order one, i will happily post it to you, from uk to you.
https://3ds.hacks.guide/godmode9-usage.html#restoring-a-nand-backup
Could you try redownload the megascript, and copy it to the gm9 scripts folder, then try restore?
https://github.com/annson24/GM9Megascript