Primitive spring lancet
The box is inscribed NBS over 1850.  The lancet is marked GAS.  If the collector isn't familiar with 19th century script you should refer to an online site that will give examples.  Several possible matches have been found for the possible owners of this piece, but none can be substantiated at this time.  
Spring lancet and case consistent with a "one-of" piece made by a local craftsman instead of a firm dedicated to making surgical instruments.