OK Paul - that is the Holly pattern in the hat shape. The Pepper Plant variation is really the same pattern but an earlier mould using a hexagonal base that is ground and not "Snapped up". The pattern differs in that the berries are pulled down into elongated shapes that got called peppers. It is the same pattern concept. The round (snapped up) collar base (marie) shows that you have the later Holly hat.
Is the base colour clear? It does look like it's amethyst.
Nice piece, by the way. Not wildly scarce or anything, but a good looking piece of Carnival.
Glen
(ps I hope I made sense - it's not easy to explain)