They're very hard to find in good condition, and to own one, your competition is anyone with an XE ESP too.
I gave up looking for a good set, and bought the restoration 'decal' from Grafix Unlimited. It's a metal-finish, stick on type deal and is only $20 (which is cheaper than a good badge if you can find one). You just stick this metal 'face' onto your existing, worn badge - make sure you clean it up well first.
Here's the link - there's a heap of other stickers for the XD XD too. I bought the whole kit for my XE and it's of excellent quality.
http://www.grafixunlimited.com.au/products.php?display=534 