The value of a used gun depends on how much an individual is willing to pay for it.
In my opinion $600 to $650 would be a fair price for a used Marlin 1894C in the condition you described.
Congratulations on buying a fine genuine Marlin rifle.I know you are going to truly love it.Please post pix when you get your new to you 1894C.

Last edited by buzardbait; 05/27/12.
Like oats through a horses ass, so are the days of my life