Any ideas where I can source them? Deroure list them but at £400 I’m just not going there… its only mesh FFS!! 
Something like this. Afraid I can’t remember exactly where I got mine from.
Made some cardboard templates, cut to size and formed by hand over the edge of some 2x4.
As far as I remember the OE mesh is steel, so quite a bit stronger and more difficult to shape than alu mesh.
You could try here:
http://www.metal-mesh.co.uk/index.php