If you are replacing the complete head unit for the HVAC controller, and that is a picture of yours in the first post, I believe you will need the one with the temperature control. The picture shows the AUTO function, which I believe you set the temperature for each half of the car (driver side, passenger side) correct? If you order without the temperature control, you will not receive the head unit with the AUTO function.
Look in you glove box where you will find the label with the RPO codes. These are factory codes showing what equipment and options your car was built with. I believe the Auto with temperature control code will be CJ2. Manual should be C67. That will tell you for sure what unit you have.
Also make sure that you order the correct part number because the Acadia uses red background lights, and the Traverse and Enclave a bluish/green light . I'm not sure what color the Outlook uses.
Have you tried checking with some of the larger salvage yards (LKQ for one)? Or check this link for a network of salvage yards. You can always call or email asking for pictures or an honest description of the parts. They may have the correct head unit for less, and maybe even the interior parts you need. Search for A/C Heater control
http://www.car-part.com/
One other yard I have used in the past for late model GM parts at a decent price, great service, and fast shipping, has been Schram Auto Parts. They used to have two yards in Michigan. They used to be a sponsor on the Acadia board, but I don't think they are anymore. Well worth a phone call to them. When searching his listings, search for temperature control head unit.
http://www.schramauto.com/