In truth, they are pretty scarce in terms of length and being permitted (CRT do not automatically grant the right and insist on a survey).
There are a few nice ones around Adlington, some just outside Blackburn and then the odd few on the summit in Barnoldswick. After that I think I am correct in saying true EOG's (not farmers fields) are next at Silsden.
My advice would be to have a reckky on a bike and then be so cheeky as to knock on doors and ask if people would be interested in a few extra beans income for no effort. Some might be happy others less so at the prospect of you tramping across their garden with your stuff.