I dont see that the fault you have had should have caused irretrievable damage to your hard disc to the extent that the "normal suspect" disc repair tools would be useless; so I'd get hold of Norton Utilities (part of Symantec Systemworks) or suchlike, load that onto a host machine and then install your hard disc as a secondary drive on the host machine and see what NU can find and retrieve.

The specialist agencies charge lots because if the internal hard disc driver card has gone a.w.o.l. they could be "mix and matching" hard disc internal components in a clean room in order to create a drive unit that can then be analysed.