If I am understanding you correctly you are talking about the gear that is on the actual blend door that the gear of the actuator meshes with? If so, then unfortunately, these are part of the door itself. You can find just the door but you usually have to remove the HVAC housing and take it apart and replace the door.
In my experience it is better to just replace the housing because you are going to pay just about the same amount in labor to have it taken apart plus you run the risk of it not being sealed properly.
If you are going to do it yourself, it may be worth it.
I included the instructions on how to replace it just in case you want to remove the housing and do it. Unfortunately there are no instructions in the manual to do the actual door. However, if you get the door from an actual company that sells them and not off of ebay or something, they normally come with instructions of that part.
Let me know if you need anything else. Thanks
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Thursday, June 13th, 2019 AT 2:36 PM