All day folks were hustlin' in and out of the Fox River Mills headquarters, many of them carrying clear bags filled with multicolored socks made in Osage. (ABC 6 News) – All day folks were hustlin’ in and out of the Fox River Mills headquarters, many of them carrying clear bags filled with multicolored socks made in Osage. Friday, October 3rd, marked day one of the Fox River Mills’ annual sock sale, an event that started over 30 years ago. The final day of operations for Fox River Mill is October 10, leaving some to wonder what will come of the sock sale in the future. The final day of this year’s sock sale is Saturday from 9 a.m. – 5 p.m.