The inside doesn't look good but I think usable, although it does look shatterd a bit at the end?
But I think you need a new rotor, and I would do bearings as well, just to make sure.
But since the 1717 isn't made anymore, finding a new rotor would be hard I think.
Are the magnets loose on the rotor, or is it just a bit damaged?
I had similar problems with my losi motor, and fixed it with good super glue.
Are the bearings damaged? If so, the rotor touches the inner of the motor.
Just soak the kevlar rovings with super glue, as long the magnets are not loose, that should be working.
try to get the Motor clean from dust and sand, that damages the rotor.