Position control on the HVAC control head of my 2001 SL2 is difficult to turn

I've been told it's the door in the case and valve and the C and V needs to be replaced.

I had a Saturn technician look at the problem and he told me the case and valve is binding up and recommended replacing the case and valve for a cost of $1,000+tax. I think that's too much.

My car is 10 years old and I don't think I should put that much money into the repair.
Advice, please.