I can't recommend an agrotourismo, but I'd suggest you consider staying in Bayeux. Very small town, charming medieval core, great cathedral and of course its famous tapestry.
We stayed at a nice B&B which was near the heart of the historic town core, very convenient to everything. Owned by a wonderful couple who were great hosts and were fascinating to talk to. And they helped us outline highlights of what to see in the area. An elegant home -- maybe larger than you need and not quite what you're looking forward to, but the town has charm and is great place for an evening stroll.
My review of the place is here: http://www.tripadvisor.ca/Show...ormandy.html#REVIEWS
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