I bought some sheets of mesh from the fencing section. Looks good, its nice and sturdy, plenty of airflow and it was easy to cut to size. I think it was about $10 a sheet and I got two shelves out of each sheet.
Sorted, found a wardrobe shelf (presume the same you used mad_at_arms) that was almost exactly the width I needed just had the cut off an overhang on one size and cut it to length