Our thanks go to Laura for finding a pair of Gore-tex socks which fit Sheila. We had been looking for a small pair of GT socks for ages, as those who read this blog will know.
If anybody else is looking for a pair you can find them HERE (just type Goretex socks in the product search). I would have put the exact page in as a link rather than just the company but pages have a habit of changing.
Much easier than ordering them from USA.
Thanks again Laura.