I inherited a model 1898 in original condition about a year ago.  I have shot it twice since then, and will probably continue shooting it maybe once or twice per year.  Here is my problem: I would love to experience the vaunted accuracy of the old Krag, but my eyes just don’t work well enough to shoot a good group with the original open sights.  I am thinking of trying the Kraghaus 3-inch sight rail to temporarily replace the rear sight, but I do not want to spend a lot of money on a scope that I will rarely use.  So, can anyone recommend a cheap scope with long eye relief that will give good results with the 3-inch rail?  That rail is advertized at $38 including shipping, and I would like to spend no more than $100 for a scope.