Greg, I got home about an hour ago and unfortunately cannot find my 60s catalogs. They're not with the others. I moved my office a couple of years ago and they must have been misplaced in the process. But I did find a bunch of other knife-related stuff I've been missing!
Sorry I can't get you the 60s display picture yet but I'll look some more tomorrow.
I'm not even sure there's display pictures in them (there weren't any in the 1970 catalog). As donjr said there are some pictures of displays in knifeaholic's book. The bad news is, the picture of a display cabinet on page 292 says its from 1968, looks to be made more like the one Keith posted and has the older style Case decal. The "XX Cutlery" below "Case" is black, not gold. If that's typical of other cabinets from 1968 and prior (I'm not saying it is cuz I don't know) your XX knives weren't ever in a display cabinet like the one you just bought.
Maybe Steve will see this thread. I'd bet he knows and he for sure has way more catalogs than me.
All in all I'd say "who cares". Put the XX knives it it - 99.9% of people that see it won't know anyway!
Ken