In the beginning of this video there are at least 3 times the tail stops spinning so it looks like it may not spin if the elevator is in neutral???
This appears to be a 3.5 channel? Finding parts may be near impossible. I know you don't want to hear this, but it's really a toy grade heli. I honestly wouldn't spend any money on repairs, but that's just me. My advice, for whatever it's worth, is to get one of the small blade helis, you'll get a lot more for your money.