Derailleur Arm Damage Question??

[BC3]

I have the 2009 XTR rear drailleur with the carbon fiber arm (plate). I recently noticed a deep scratch with some fraying on the edge (I think I actually remember the rock that I hit). I "flex tested" it with moderate pressure and it seems to be structurally sound. I figured I should probably repair it as it is not a part you want to give out during a ride. Is this a difficult repair? Can I order this part online for a DIY home repair or is this something better left for the LBS?

BTW - I went on Shimano's site to get the part# and I noticed the 2010 version switched back to an aluminum plate. I guess they figured CF isn't the best material to have in such a highly vulnerable spot.

 

[DISCO]

I'm in the market for a shorter cage for just that reason.

I spoke with Jim, the Local Shimano Rep at Fontucky and he affirmed that aftermarket replacement cages are in the catalog and should be available from any LBS as a special order.

Looks like Shadows may still be carbon only, won't ride any other.