Stepper motor and driver for air flow control damper/valve

im looking for a high accuracy stepper motor and driver for air flow rate controller to be installed in vav box. The damper/valve needs to be modulated/controlled from 0-100%

Use any.

You have given us no information about the force that is required to move the damper valve.

I believe the cheap 28BYJ-48 stepper motors and ULN2003 controllers are used for that sort of purpose - but if you want to move a large valve in a strong airflow they may be totally unsuitable. There are lots of Forum Threads about 28BYJ-48 motors.

...R
Stepper Motor Basics