Need an actuator for ac, yes its still need in fla

[bamafutbal]

driver side blows vent air while the passenger side blows cold air. took it in (under the 90 LIMITED warranty another chevy dealer gave me) and they said it will need an actuator and its not covered under the warranty and bill will be 460.00. i passed, now just turning off driver vent and using the passenger vent to blow cold air. anyone else have this problem and is this a part that is easy to get to.
john
07 ltz tahoe