This is what caused my confusion (
http://www.ebay.co.uk/itm/VOLVO-S40-...091939#vi-desc).
The part code is the same as on my C70 but it is listed for an S40/V50 2004-2007.
At that price it's a third of the cost of a new part. But i just need to be certain rather than end up with a part i need to sell on.