Thanks all! Memories, eh?
Hi Moh
Yes, I saw that scene as well, and recognised the one we photographed in it. I guess that there were only three X-15's all up that saw active flight, so chances were pretty good. If you look for more photos of this actual aircraft, you'll see it in various tail trims and livery. Experimental planes must really undergo change from time to time as part of the development cycle.