If you are talking about a Open Mouth'd look with out a Badge in it then you can buy them in the UK from places like
www.tuning.co.uk/vauxshop thats where I got mine.
It includes everything to make the grill ready to fit including the Mesh.
You can also get a grill with a Open look to it like the one above but with a Centre section ready to be able to fit the Citroen Chevrons (Two Arrorws) so it looks like a standard grill but with the Slats removed.
Either will look good with Black mesh, personally Id avoid Silver or Chrome mesh as it looks tacky.
Hope that helps