I’m not entirely sure how reformatting an ext4 disk to NTFS would help recover data, but…
Here are the two threads I’ve been hanging on to for unbricking.
Fox_exe here:
Or cnlinya here:
http://community.wd.com/t5/My-Cloud/How-to-unbrick-a-totally-dead-My-Cloud/td-p/651195/page/5
I don’t think it’s necessary to have the exact size image: most of the guides discuss resizing once you have the device booting.