FWIW, my grandparents came from Friesland and my mom and aunt both had porcelain dolls. They did indeed have the holes in the head for the hair, so perhaps it's something more scarce to find, or maybe it was only done during a certain time period, or region.
I remember it distinctly because when I was 5 or 6 years old, my sister pulled one out of an old wooden trunk. I was totally weirded out not only by the look but by the holes in the head. Then an earwig crawled out of one of the holes, which is why earwigs still freak me out to this day.
