N6001C (US registrations normally written without a hyphen) was just the first of this batch of 20 Connies, delivered in March 1950, the remainder followed at the rate of around two a month. Like most of the others, it remained in service (latterly just confined to domestic services, of course) until the mid-1960s, in its case September 1966, and like N6007C described above was parked up at TWA's Connie maintenance centre for a couple of years, never found another buyer, and was then broken up for scrap in 1968.
Looking at the 1955 timetable it appears this flight was numbered 967 for the Thursday arrival in New York Idlewild (nowadays JFK); it was 963 on other days of the week. A typical westbound overnight schedule of the times, the TWA timetable shows an optional stop at Shannon, but does not mention Gander. However, the various stops on transatlantic flights of the time were notably flexible depending on winds, and often bore little relation to the published timetable (the same applied to the arrival times). You will find the complete TWA 1955 westbound summer transatlantic schedules here ;
http://www.timetableimages.com/ttima...55/tw55-19.jpg
http://www.timetableimages.com/ttima...55/tw55-20.jpg
click on the images to enlarge them. Note that First Class and Economy ("Sky Tourist") were operated on different aircraft at the time.