Yes the white coating is accurate along with the port cockpit window being covered. The X-15A-2, was modified from the number two aircraft and delivered to NASA in February 1964, included among other new features, a 28-in. fuselage extension to carry liquid hydrogen for a supersonic combustion ramjet that was flown (as a dummy) but never tested. It also had external tanks for liquid ammonia and liquid oxygen. These tanks provided roughly 60 seconds of additional engine burn and were used on the aircraft's Mach 6.7 flight.