Well, I work in a plant nursery, so I have some sense of it (not perfect!).
We're in North Yorkshire. Where I work, a tree at 200-250cms costs £65. Our mark up is usually 2.2, which is industry standard, and a bargain when you consider how many hours of work it takes to unload trees, tidy them up, set them onto a base, and so on.
We also sell trees we have grown, and we price per foot. I don't know the prices for this year yet, but they are generally competitive.
It is not easy to grow a good Christmas tree. We put a lot of work into them.