bulk galahad flour

Try your local bakery, they may have it. If they do not, they maybe willing to order you a bag on their next delivery.

The name of your town is certainly appropriate for a baker!

You could try calling one of these foodservice distributors to see if they carry the flour and if they will sell to you.  

Associated Buyers, Barrington, NH, 603-664-2424
Favorite Foods, Somersworth, NH, 603-692-4990

I can't speak to local sources in NH, but there is a website I've used called The Flour Sack that sells Sir Galahad and other King Arthur flours in various sizes from 5 lbs to 25 lbs and it tends to be less expensive than buying those little bags directly from King Arthur.