Gunston Hall:  Your sporterized Krag has a Redfield 'no-drill' model 102-k commercial peep sight on it.  This sight is worth $75 to $100 with its attachment screw.  If the bore of your rifle is good,  you have a useful sporter/shooter worth around $300, as is, to some Krag enthusiasts.  Its value is strictly utility and parts.  Some of us like the old 'Deer Rifles'.