If you look at the top of the page, there is a facility where you can search for campsites. If you look for North Devon, there are 3 pages with sites there, not all in the area you are looking for, but there are some. Damage Barton for one, is a really nice site in my opinion.
Amazing family weekend with old steam engines, classic car displays, market stalls, and full catering and bar. And camping on site - Save £25 by booking in advance.