Thanks everyone for your replies. Sorry it takes me so long to respond, I've been pretty busy lately.
In any case, to answer the questions. As for what I want, I would like $150/mirror to get out of them. If I were to continue making these, I'd probably be at the $200 mark. I currently have 8 full units (head, base, backing plate and internal hardware). If necessary, I could come up with 5 more (I'd have to have a few more bases and backing plates cast) but I'm not really intending on that.
As for the mirror internals, they are not the same as the original. The original ball-stud was a push/press in spline. These are a threaded ball stud that is set into a hole in the back of the mirror head. Something like JB Weld would hold it in. In my test unit, I used silicone as a glue and it held great. I was also able to take it apart.
The base is solid and the head is screwed to the base instead of the other way around as in the original. I'm attaching a bunch more pictures that should show how it is put together.
Thanks again.