Maybe something else was damaged when both failed. How long was it driven like that?
CSB's are wear items, I'd say every 3 - 5 years. The flex disk might fail on my e30 every 10 years? I've only ever replaced one. Given that your car is 10 years old it isn't out of the question. Now you may have other issues with the transmission, differential, or U/CV joints on one of the shafts.
Performance one step at a time.