I've been looking for that for about four years now. Not much success; certainly not for the period. Closest I've come is the group "Mediaeval Baebes". I'd recommend them to you though they're not of-period.
Anglo-Saxon Folk is not as popular as Celtic or Gaelic Folk, or really any other folk music in a global sense. I guess the Angles, Jutes, Frisians and Saxons aren't as glamorous as the Norsemen/Vikings, so nobody does folk-metal either. Generally, if you can't find authentic folk you can find folk-metal, but no joy there either.