Hawick's has two well known associations with kilt hose. Kenneth Short Hosiery have their factory in Commercial Road, Hawick, and they sell their products through some of the local quality knitwear shops. They do not have their own retail shop but appear to do mail order from a workshop at the home of one of the proprietors. They are well known for supplying kilt hose to pipe bands throughout Scotland and indeed one of the partners in the business plays with Hawick Pipe Band.
http://www.kshosiery.co.uk/
Hawick Sock Company is I believe entirely independent from Kenneth Short Hosiery. I think this is the name of the specialist business run by Robin Deas, from a small workshop in town, and which produces hose in more limited quantities than Kenneth Short, mainly for export, to specialist suppliers such as Matt Newsome. Matt can maybe correct me on this.
Both Kenneth Short Hosiery and the Hawick Sock Company are highly respected brands of quality hose.