This is the .25 ACP pistol, right? Not the .380 ACP.
I bet that it depends upon the date on the sales receipt. Older is probably more valuable.
Without the box or receipt, the gun seems to be worth between $350.00 and $500.00, depending upon condition and age. (Reference: Standard Catalog of Firearms)
If the outfit is old enough, maybe add $50.00 to $100.00 for the box and receipt?