Here are details of some nurseries that sell Meconopsis plants. Some have a much larger range than others, so it is a good idea to check websites.
Meconopsis plants can also be bought at shows run by the Scottish Rock Garden Club and the Alpine Garden Society, and at big flower shows, particularly at those held during the flowering season, such as RHS Chelsea Flower Show and RHS Malvern Spring Festival.
There are also often plants for sale at our own Group Meetings.