Marvin (https://www.marvin.com/) fiberglass windows are available with black exterior and interior finishes.
Westeck (http://www.westeckwindows.com/) appears to make vinyl windows that are black on the exterior and interior.
It is my understanding that at one time -- maybe it's still the case -- installing dark-colored vinyl windows on the sides of a house that were exposed to the sun was not a good idea. This was because vinyl is not thermally stable so the windows expand and contract with changes in temperature. Over time, this caused the windows to break down (e.g., the glass became loose in the sash). Fiberglass windows are stable so dark-color exterior can be used safely.
Soft-lite (http://www.soft-lite.com) does make vinyl windows with black exteriors but not black interiors.
Q
