According to the book Canadian National Steam Power, by Anthony Clegg and Ray Corley, the CNR owned seven 0-4-0Ts, numbered 1,3, and 36 to 40. They owned only one 0-4-0, number 2, which was scrapped in 1922. All of the tank engines were gone by 1930.
As for 0-6-0s, there were 459 of them in 1923, 393 in 1933 and 282 in 1943. Numbers ranged from 7000 to 7699, although not all numbers were used. As you can see by the number of locos in service, the totals declined in later years. This was in part due to the introduction of 0-8-0s and later diesel switchers. If you could let me know the area which you're modelling and an approximate time frame, I'll try to give you some more specific locomotive numbers.
Wayne