I personally believe that this knife is a bit earlier, circa 1951-1958. The stamping with the crown over the "i" and the vertical "USA" was noted by Goins as being c. 1954-88, but I think this one is on the earlier side. It is odd that the pocket chain survived, if it is original to the knife. These chains are most often seen on knives of the earlier part of last century.
Don't ever be reluctant to show a cheap knife here, especially one in excellent condition with original packaging. It was the cheap knives which built Imperial, Schrade and Camillus. They are an important part of the history. And because the structure was less robust, they seem to be even more uncommon that the hiigh-end knives these days!
I suggest that you take this over to the Levine forum and get his opinion of the aproximate age. He may concour with my opinion or set me on my ear, either of which is welcome!
Michael