Sorry I can't help much with a value, but the box is correct for .45 Schofield cartridges. The first loading of this cartridge by Frankford Arsenal was in August of 1874.
.45 Schofield (dimensions are approximate):
Gilding metal case ("copper"), inside primed (Benet primed, crimp marks forward of rim), no headstamp. Lead, flat-nose bullet, 230 gr.
Case length: 1.10"
Rim dia: 0.517" (early); 0.522" (late, slight bevel)
Currently there are two similar, sealed, boxes of .45 Schofield ammo listed for sale at $300 - $425 on Ray T. Giles's website. Of course, condition plays a strong part in the value.
Hope this helps.
TL
