If you have the files on your hard drive you are still able to recover it i think.

You should buy a new hardware like the one you have and do a full clone, to let the original one untouched, then try to recover the files of the new one (the cloned one) with software like recovery my files , recuva...

Maybe you can find something. As far as i know even if you format a hdd if you do not write data on it again the old data its fully recovereable.

Sorry to hear that story mate