Hi Andy, they look very nice and a good variety of shapes and timbers.
Part of the pricing equation is the type of craft fair, where it is located, other sellers, expected customer profile etc, as well as time of year !
My complete guess is, and others will have their own ideas and experiences, that between £15 to £50 for most, depending on the context of where you are selling. Well finished, well proportioned pieces from interesting timbers could well fetch more in upmarket or well regarded galleries, whereas a small local craft fair with limited footfall and in a not particularly well to do area might see you struggling to move any regardless of price !!!
You can also try pricing reactively, start high or low and adjust pricing over the course of the four days depending how it goes, but decide beforehand the minimum prices you would be prepared to sell at or at which you would rather take them back home again ?
Good luck !
Cheers, Paul