This is a follow-up to my post on Irving Oil tank cars.
SteveO found a couple of great photos of Irving Oil tank cars online and shared them with me.
First, Irving Oil tank cars in 1966. They are labeled as "new tankers". The Irving Oil refinery in Saint John was built in 1960, according to Wikipedia.
The closest car is NCTX 22514. It looks like the other three are also NCTX cars.
Here's one showing Irving Oil tank cars being unloaded at Edmundston in 1971.
The tank car in the foreground is CGTX 20578.