While I've never set up a display yet, I've seen a lot of the office swivel style lamps being used. Long ones can sit up above the typical buyer's head height, and be out of the way.
Whatever you decide to use, set it up beforehand with a temp probe IN the delicups to test to make sure you won't microwave your snakes on display with the heat from the lights being reflected in the cups. There's not a lot of ventalation in a delicup so it will tend to hold heat in.