All involved with this project have been unable to dedicate the time required to move this forward.
As such, we have adjusted our expectations to complete this... sometime.
A mass of different BLDC and micro stepper motors were ordered on the slow boat from China, arrived, and one was modified with good results. 11.9g with a hollow 2mm shaft.
The chips required for our preliminary design are in hand and are waiting on boards and firmware to be authored.
A new 3D printed base/mirror mount still needs to be designed.
This will get done, but it will get done when we all have enough time to do it. I don't know when that will be right now.