For value, 1st thing to do is confirm the serial # stamped on the back of the right stock matches the gun #.
Assuming it does and since you have the box, in that condition, which does look un-cycled as well as un-fired, it's a highly desirable model. The only ones more desired are the 1st version Improved I frame with round sight, and higher than that is the 1st post War Transitional 6 screw with leaf main spring.
But I'd say, and depending on location, it's in the $800 -$1000 value range, possibly higher.
Much more detail here:
http://smith-wessonforum.com/blog.php?b=103