Replacement rotor for 1515 2200Kv motor ?

Hello , I was racing last week and all of a sudden my truggy was acting like the driveline was binding and started making a weird noise , after the race I went back too the pits and started looking for the problem , gear mesh was correct , diveline was totally free , the motor seemed like it turned ok .

Put it all back together and started too run it on the stand , everything seemed ok but then when it gave it more throttle I noticed the motor shaft moving out like 1/4 of an inch !

So I took off the front plate and pulled the rotor out and it seems the magnet has seperated from the motors shaft and that was causing the shaft too move forward and come out of the rear bearing and would start too rub the coils inside the motor can !

Its never been over heated and the bearings are still in great shape ? Has anybody else had this happen ? Can I buy a new rotor from Castle or NUE ?

I dont want too throw it away cause all it needs is a new rotor ?