It's not worth it, It's a £550 car. I can get a new engine for less then the cost of a genuine belt/pulley kit & labor cost. I can fit the engine myself.
The belt has no wear on it, even on the inside no cracking c (I know it doesn't stop it snapping or breaking just because of that). There's no proof of it being done, but that doesn't mean it hasn't been, there's countless clio's that have it done with no proof. If it was a very clean, low mileage, sort after model which was worth a bit, I wouldn't hesitate to get it done straight away.