It is difficult to trace, when the kilt was first worn. It may have been in the 1500s, when it was more of a long length of plaid cloth that was gathered about the body. In the 1700s, it became more like the kilt that one is familiar with today. When dressing in Highland Dress, one of the pieces of this wardrobe is the kilt socks. These are available from more than one source.This article shows where to buy kilt socks
According to Cuillian Craft, "Day-wear Hose (stockings) for casual or formal day-wear may be of any colour, although most are of light shades, including lovat green and blue, tan, or brown. Today, hose of off-white or ecru are preferred, usually with traditional or celtic patterns, however, for more formal day dress, the hose should match the colour of the jacket. White hose have been popular because they were given away with kilt packages for hire. White hose are NOT considered correct for highland dress except by civilian pipe bands, and even then only under duress. The hose should come to three inches below the BOTTOM of the kneecap, folded down at the top." Cuillin Craft offers the Pibroch interlace pattern hose, the Braemer checker top pattern, Fearg hose, and castellated hose. These are hand knit for the company. Additional colours include "white, lovat green, lovat blue, charcoal, burgundy, oatmeal, ancient green, and fawn" as well as any colour that you desire. The company also offers men's kilt as well as kilt flashes.
Dunadd Trading Company
The Dunadd Trading Company carries diced hose, clansmen hose, Bowmore & Chessboard, Argyle Tops Kilt hose. Some of the kilt hose is offered with a choice of colours. Other items are offered as well, such as kilts and other items of highland dress, with a selection of kilt patterns.
Twenga states on its website that it is the "The Biggest Choice Online." The site is a collection of stores which is able to offer 277 different men's kilt socks that range from traditional hose socks, a Northumberland Sock, wool kilt socks for men, weathered kilt flashers, merino wool socks and more. The site offers a bewildering selection of kilts, loin clothes and other items.