Hi ben what are you doing with the flaked barley?
You could just leave it out and use extra pale malt.
I think flaked barley does not really do that much for any brews. saying it aids in head formation and rention doesn't really mean much to a all grain brewer when the base malts etc we use will give you a damn fine dense head anyway.
Flaked darley will not add anymore body.
You could try your supermarket for it or just leave it out.
I would be happy to sub the torriefied wheat for flaked wheat but don't have any experience with flaked wheat as such.