This is the kind of thing that is worth heaps when you want one and nothing when you have one.
I couldn't find a set anywhere, eventually bit the bullet and paid a ridiculous $400 for them. About 6 months later I had 2 more sets (which I had no use for) and two friends with unneeded sets.
Hold out long enough and you'll probably find someone who'll give them to you for a carton of beer.