Getting parts is tough these days and getting a set of rotor blades that are 505mm long with 8mm roots is almost impossible.
I bought my SX in 1990 and flew it up to about 10 years ago when i had a battery failure which damaged it quite badly. I have spent the last few years gathering parts together to repair it one last time, simply because of the problem your having now.
You dont say if your an experienced heli flyer or not, i'm guessing you are as learning to fly using the concept is not going to work
I did a little rebuild here that may interest you -
http://www.rcaircraftonline.co.uk/sh...ge-Restoration
Which concept do you have ?