I assume these are the ones that have the raised WRC Tarmac logo? They come in two types, the common 5 spoke and the rare multispoke. Should be 17x8. I must admit, only heard of two other multispoke sets besides my own, pretty rare.
Some people sell standard wheels off the 8's and 9's for £500 and thats a run off the mill wheel. They are worth as much as people are willing to spend. If they are the multispokes, I would keep them.