I guess that they're rare enough to warrant buying what ever you can get but it looked expensive compared to what a big tank for a KTM exc is worth but cheap compared to one an F650.
I keep thinking that I want one for the XMoto but then I usually walk by that and get on the F650 out of preference now that I've ironically taken the big tank off of it.
That is cheap. A friend has a brand new one, fitting kit still in the bag with the instructions.... it is in the back of his container, totally unused.