I used exactly 516 yards for mine. They weigh 118 g. I didn’t use the entire third skein. (Added because people were wondering if a skein of Wollmeise with 575 yards would be enought.)
March 3rd 2012: A portuguese version is now available here: http://tricoemprosa.com/traducao/meias-lakeside/
October 2012: An Estonian translation is now availble here: http://helenapesa.blogspot.fr/2012/10/julia-vaconsini-lak...