Well from Durham, you could possibly come on up to Edinburgh as the Edinburgh Festival Fringe starts on 1st August. This includes nightly folk music concerts in The Royal Oak pub downstairs lounge. Only £6 per ticket and you get a good 2 and half hours of entertainment. There are several other pubs nearby where folk music is the usual genre of music, and of course there are hundreds of other events on in the Fringe.
The main problem would be finding accommodation at a reasonable price as the city will be very busy - and expensive!