The early-mid-60's gun I've seen was merely an opened up commercial FN 98 .30-06-length action with the common thick stock of the day, quite similar in fact in overall appearance to my son's FN .270. The main difference ws in finish, where the stock had a thicker, shiney "varnish" of some sort.

Nice gun IMO. Beware, tho. Those experts can help us, but I believe a few may have been fitted with salt wood? I don't recall 100% if any of the bolt guns were.