If you fancy a trip further afield, Somerscales in Grimsby/Immingham were excellent when I went, on the recommendation of a couple of other forum members. They will take packs down for you and help you look through. Prices were keen. I got a few boards of different things in the car to make it worth the trip. Unfortunately I want some more of their cherry, but it isnt really worth the trip to go for just a couple of boards.
It also depends a bit on what you want. They had a lot of native timber, and some imported, but nothing exotic. For a single board it may be worth paying top wack and just getting it locally. In most cases, the cost of the wood is tiny compared to the work that you put into the finished piece, so you could spend a day trying to save a tenner. I find lavers a bit pricey but they do have a decent range, it is 2 square edged so cuts down on wastage and it is handy.
You mentioned making a chopping board in another post. If you cant get enough offcuts to make it, why not get a board that will allow you to make a couple more and use them for presents. They would make a great wedding present, christmas present etc. Offcuts can be great, but sometimes it is far easier to get a full board, machine it as a single length for your project and use your own offcuts for the next project, rather than trying to make things work from bits and pieces. Some projects are easier to do so than others.