When I can't find what I need, I make it myself. I would go to homedepot, buy 2"x4" board and wire and screws. Then make a wood frame, screw some screws on it on needed distance and connect them with wire. You could make squares any size you want.

@avgusta_gw That's too much work for the limited use I will get out of this.

Another options- buy a storage plastic bin from walmart or a metal tub from tractor supply, and drill holes in it aka in the collander.

Maybe look for a milk crate or a bread tray. Those can have around 1" holes.