It is definitely not a long term solution, as the firmware will not match the bad sectors on the platters. It is a quick and dirty fix to attempt grabbing the data, then dumping both drives.
However, assuming the EEPROM is salvagable from the old drive, you can attempt to migrate it to the new PCB, thus resurrecting the drive. I still wouldn't use it for mission critical storage, but it would likely suffice for a scratchpad drive assuming there is no platter damage.
Still, I would attempt to get the data, then toss both drives. You are out the price of the donor drive, but at least there is a chance of data recovery at a fraction of the cost of professionial data recovery services.