If the socket is too far gone to be repaired (if the metal is fatigued), then the best solution would be to have the existing socket removed and a new socket turned from brass rod to fit the crook tenon. This may cause loaclised lacquer damage which can be cleaned up and oversprayed to make it less obvious, but if the socket can be fixed by hard soldering a piece of brass into the slot, machining the inside true and then recutting the slot (but not as deep as before), the socket will still have to be removed to do this, so the lacquer will be damaged in any case.
A lot of the time sockets on baris get damaged as the weight of the instrument is concentrated on them when being carried around in the case if the socket screw rests against the back of the case. This can cause metal fatigue and the best solution is to have the socket removed and turned around so the screw is nowhere near the back of the case, but still accessable so it can be tightened up. I did this on an X-bar bari where the socket was too far gone to be patched up, so I made a new socket and fitted a Yamaha socket screw as these are large, and positioned it back on so the screw is round towards the front of the instrument rather than being right at the back where it's vulnerable to damage.
So check the case for wear at the back by the socket screw and place something in the case (such as high density foam blocks) to distribute the weight of the instrument along the length of the entire body and not just concentrated on the socket screw and Eb keyguard (which also takes a lot of abuse from ill-fitting cases).
A lot of the time sockets on baris get damaged as the weight of the instrument is concentrated on them when being carried around in the case if the socket screw rests against the back of the case. This can cause metal fatigue and the best solution is to have the socket removed and turned around so the screw is nowhere near the back of the case, but still accessable so it can be tightened up. I did this on an X-bar bari where the socket was too far gone to be patched up, so I made a new socket and fitted a Yamaha socket screw as these are large, and positioned it back on so the screw is round towards the front of the instrument rather than being right at the back where it's vulnerable to damage.
So check the case for wear at the back by the socket screw and place something in the case (such as high density foam blocks) to distribute the weight of the instrument along the length of the entire body and not just concentrated on the socket screw and Eb keyguard (which also takes a lot of abuse from ill-fitting cases).
