talk to vec over on bladecprepair.com he used a steel shaft out of a cd rom drive, and he's wrecked his heli so bad that it's been a complete rebuild, but no bent main shaft =) He's also got a ton of other mods that make the heli so it can take a good crash dust off and get flying again.

btw I didn't read all of this, so sorry if my post doesn't exactly answer what you are looking for