Where to buy screen grids for c&c cages?

i am going to make a cage like this http://www.youtube.com/watch?v=5gtqpOpzrzI&feature=channel for my baby rats... however i think they will squeeze threw grids of this size http://www.kc-store-fixtures.com/mini_grid_displays.php ...is there an online site were i can get those grids but with screen instead of the coated 1" X 1" spaced wiring? Thanks!