Chris,

I'd say more probable. Of course you can't rule out a blade forged and ground that sat in the bin for a while, but at the same time you have to consider all the evidence at your disposal. Take a hard look at Stephen's 1-7 knife and sheath (Which has the horizontal Randall stamp) in the middle of the below photo:



That sheath has characteristics that no Johnson sheath I've ever seen has (The "countour" for example). The blade has a nice deep choil and the model is one that was very popular at that time of the Vietnam build up.

Also, didn't realize you were in the shop in ~ 1960.