Electronic stability control light on, steering angle sensor cannot seem to find?

I bought this car from a dealership and noticed the ESC light was on as i was leaving. Then i noticed that when i first take off the car pulled to the right. The dealership had the car aligned and attempted to put a new steering column in, but they say the sensor on the column was faulty. They ordered another column, and it arrived without the sensor. They say all the problem is a steering angle sensor but i or they can't seem to find this sensor anywhere. Can the sensor be replaced without buying the column? Where would we find this part?