Excellent getting that ISP gun and box reunited. A lot of effort and a little luck made it happen.
I have told this story before, but in December of 2007 I purchased a near new Colt Woodsman Sport Model made in 1948 at a local gun shop. In July of 2010 (2 1/2 years later) I happened to be perusing ebay and looking at the prices that vintage gun boxes were bringing. I saw a box for a Colt Woodsman Sport that contained the numbered test target and manual. I thought hmm... that serial number is close to mine I think. I checked my gun and it was the same serial number ! Needless to say I won the auction. I contacted the seller who happened to be in a town about 20 miles away, and told him where and when I bought the pistol and asked if he would share how he came about owning the box.
In fact I emailed him twice and received no response what so ever. The gun shipped to a hardware store in Quincy Illinois and ended up in a SouCal gun shop almost 60 years later, and got separated from its box & test target along the way. They are now back together