The shell is available at modest cost and not that difficult to change everything over but you'd need a few small tools and good eyesight/dexterity.
If the camera and gimbal were damaged it would almost make more sense to buy another drone especially the way prices have dropped lately.

I would caution that sometimes there is more damage than immediately apparent in a significant crash and it might still be the best option to get a drone only package from DJI.
In fact I think I'd do that and you'd still have the old one for spare bits.
Also a lot are coming up on ebay as owners trade for Phantom 4.
http://store.dji.com/phantom-accessories?from=menu_products