In reply to Reader_Rambles:
Keswick area, Burns Farm and Setmabanning are really good and if you only have a tent I would be amazed if they are totally full? The sites at Stonethwaite are both good. The one by the river can be noisy, the other is quiet, as you are interviewed before pitching (in a good way!).
We like Gillside at Glenridding, but so do the mice so have a thick groundsheet!
If you do wildcamp, think a bit laterally. All the Tarn spots will be busy that week, so maybe give Angle Tarn (both); Grizedale Tarn etc a wide berth.