Kastor/Camillus made them for Sears & Roebuck with the Made in USA stamp from 1924-1965, going by your can opener I with a nail nick instead of a post I would guess 60's but that is only a guess, I have one and it has the three piece can opener, they are nice knives, yours looks like it is in good condition, the bone on one side of mine is missing a chunk and my can opener is only 1/2 there, blade takes a wicked edge, Nice find.
Pete