I think thats an excellent price. I had a look on autotrader earlier in the week to see how much my car is worth at the moment, and based upon what people are trying to sell the 2007 ones for at the moment, mine is worth about 16 ->16.5k. Yours has higher mileage than mine, so id say about 14k->15k is the right sort of price.
Of course, it depends on whether anyone is looking for one at the moment and what they are prepared to pay. Yours is a good spec and a good colour, so fingers crossed.
With me doing over 250 miles a week i dont want it to hang around to long as the milage will invrease ot each month.
The prices for them vary so much as well from what ive seen so its hard to gauge a good price.