I got one time a 2.5" HD that was in RAW. All the files were gone suddenly ( maybe an electric problem) 

i found a software called "Hard Disk Low Level Format tool" that helped me very much, really it saved my life.

i was able to recover the disk & all the files, but effectively not all the files were recovered & i had a backup. 

But i don' t know if it applies to you, i am not specialist for recovery. 

I will not say to you "try one shot with this jewel!" i will be responsible if you lose everything...

on the site it is a disclaimer. it applies to me too. 

"WARNING: After running this low level format tool, the whole disk surface will be erased. 
Data restoration is impossible after using this utility! "

So I advise you to continue to search good ideas ...or go to a recovery specialist surgeon.

if the value of your files is so important that you can pay for.

Try "hddguru" on google to find the soft.

i hope it can help.