Yes, the tops of the stock cracking off is a common issues on the nitro specials. From a parts a mechanical standpoint, they are very simple guns and many parts can be had. Firing pins can break. The gun should not be dry fired. The intros are single bolted through the rib extension and they are prone to loosening up.
If this gun works well now, then it should serve you well for a long time.

B.Dudley