The keyboard probably needs replacing. When a key goes it's usually accomanied by the others on the same branch of the keyboard matrix.
The connector is probably not the issue and if it's become damaged, which is possible, there's nothing to replace as the cable usually part of the matrix and only plugs in at one end (to the computer motherboard).
Replacing a keyboard is simple enough if you can extract the incumbent without damaging the computer case and get a replacement. Take great care not to damage keyboard and mousepad/pointer connector on the motherboard.
Method varies with machine -- which is why you should probably give the job to a dealer who knows the model and can get parts.