Does anyone know where I can find a cheap replacement for the metal sticker/GPS antenna mount that comes with the X920BT?

any small sheet of thin steel will work, which you should be able to get at any hardware store.

any small sheet of thin steel will work, which you should be able to get at any hardware store.

Certain types of metallic tape will also work...not sure about aluminum though...it may need to be a ferrous metal...

They must sell replacement adhesive ground plane stickers, though...not seeing any on eBay or the Web so far...