If RJMan or Voxsartoria happen to be around, they may well know about them as RJ has spoken about Holliday & Brown in the past and Vox has mentioned S&S at length in previous posts.
H&B are irritatingly rare, as for my money, they make ties of equal quality to Drake's but they are both cheaper and wider than Drake's current selection.
There are a few department stores in Japan that carry Holliday & Brown and so I've picked up a few from there on trips over the years - but of course, that is of no help to you!
Holliday & Brown were, I believe, taken over by an Italian house some years back. They have a website, but it only has a front page and a contact e-mail address, with no further information.