Looking for Maria's necklace, or something similar!

I love Maria's necklace, and I found out that it's a Vivienne Westwood design, but I can't find any in my price range for sale in the US. I've checked Ebay, but the variations of the original that I like best are all too expensive. Has anyone seen anything similar to what she wears, with the glass orb in the middle of the metalwork?