Looking it up in the Mueller book I found out it is called a "hochgeschlossener Rundkragen" (= high closed round collar). A slipon collar is very similar but would have a very short revers.
There is everything you need in the scetch:
Draw a straight line starting at W, distance from U will be the stand width (~2,5cm). Length is back neck line+front neck line(c).
Draw the curved line through U to c.
Draw a perpendicular center back line to this curved line. To the left mark the stand width, to the right mark the collar fall width (about 5cm).
Draw the rest of the collar according to the scetch, the (perpendicular) width at W will be about 7,5-8cm.
I think this collar will be quite straight and will need quite a bit of ironwork, especially stretching the outer edge, to achieve the round shape that is needed.