Why don't you do what any Armourers shop would do when a grotty bayonet and scabbard was returned to the Armoury. Strip it down, reassemble with the grip nuts and bolts and catch nut and bolt (less spring) bead blast it, phosphate it, paint the grip/handle black to a point 1/2" below the crosspiece, oven bake it, assemble with new (?) grips (- or make some new ones from beech or birch). Same with the scabbard but remove the mouthpiece spring and assemble the mouthpiece. If the screw thread is stripped and you haven't got a replacement, just drill oversize and soft solder in place an insert to re-drill and tap 6BA later.
Then you have a well used but perfectly serviceable bayonet that's just been returned to the unit from the REME workshops or Ordnance ready to give you another 40 years service. On the other hand, you could have a grotty old worn out, down at heel ex Indian Army bayonet that's shouting out misused and abused.
The makers mark of M/78 is on the pommell!
BDLwith his facilities and spare parts could do that in a few moments.