If you are unable to visit Kazan during the month of October, then departing from Canada during the month May is also very affordable. Most momondo users find prices during this month for around 1,341 C$.
The cheapest day to depart on your flight to Kazan is on a Thursday when prices can be found for as low as 1,294 C$. This is often the case because there is less demand to fly during this day of the week. Flights from Canada to Kazan on a Tuesday will generally be more expensive and average around 1,672 C$. Keep in mind that these prices on both days could fluctuate depending on the season and the demand.