Can Yamaha MC-5 and MC-9 cartridges be re-tipped?

Hi All,

A few questions about the Yamaha MC-5 and MC-9 cartridges:

- Can theses cartridges be repaired if the cantilever has been broken off?
- if yes, approximately what is the cost?
- would it be worth it for either of these cartridges?

I know some of the Yamaha's had Beryllium cantilevers, are they 
superior in performance?  Can they still be replaced?
Not sure if either the MC-5 or MC-9 had these?

Any info would be appreciated.

Cheers,
AK