Here is the resulting curve for the teeth, in Red color.
Lopped off the top and did a fillet.

I think that does it, within some level of precision. :-)

- Brian

Edit: There is probably some formula for the curve, derived from "instantaneous velocity centers," or something.
There must be some formula for calculating the pitch circle diameter. (?)

There is a paper that did something like that for epi and hypocycloidal speed reducers