I couldn't find a brick extender for my Vivint doorbell camera so I put this one together really quickly. I included the OpenSCAD file so you can modify it to fit your situation. My camera was installed with 1" wood screws, which I replaced with some 2 1/2" screws. In my case, the doorbell was mounted on top of some trim molding. The molding is somewhat wedge shaped, so that's what the offset_size parameter is for. It renders an extended edge on one side to account for that trim molding. If your doorbell is mounted to a flat surface, set this parameter to 0.
I didn't measure the screw holes for aligning things, I just put the screws through the holes in the camera base and manually lined them up with the original screw holes on the wall. An ambitious designer should feel free to modify this to make it a little easier to install. I was more interested in getting it done than in making it pretty. =)
I printed mine with PLA since it's going under a roof, and doesn't get any sun during the day. You probably want PETG or something if you need to take weather into consideration. As long as the model is sitting on the opposite side from the one that has the offset, you won't need supports.