JemJem offers six pairs of Unisex Ankle Compression Socks in seven colors for $16.59 plus $1.99 for shipping. (Groupon charges less than a buck more shipped.) That's $3.10 per pair and the lowest total price we could find for the quantity by $41. They purportedly ease pain from plantar fasciitis and improve blood circulation. These moisture-wicking and anti-bacterial socks are available in sizes S/M and L/XL. (S/M fits women's shoe sizes from 6.5 to 9.5 and men's shoe sizes from 5 to 9.5; L/XL fits women's shoe sizes from 10 to 13.5 and men's shoe sizes from 10 to 12.
Don't mind waiting for your deal? Boboyard via eBay offers individual pairs in Blue for $1.36 (S/M) or $1.45 (L/XL) with free shipping. These items ship from mainland China and require three to eight weeks for delivery.