This grower is sure of this plant identification.
These self-seed in my garden from one I bought at a plant fair. I would have to charge postage extra, and that would depend on the pot size/ plant size.
Wood dock, Dock
Rumex sanguineus (Wood dock). A member of the Dock family; it grows wild in Northern Europe.
They will thrive in full sun with moderately fertile, well-drained soil. You can propagate from seeds which should be sown in spring or by division in autumn.
Italics = data drawn from parent genus or speciesView Full Plant Finder Record