After reading these post..I thought I would add....
This past Spring I attended an Amish auction that had hundreds of poultry..being a frugal group, some of the birds were crated in Tomatoe boxes that had a large section removed from the top..maybe 6in by 8in.and wire attached to it with zip ties..this seemed to work great..as there was different types of wire used I would say it was probably scrap.
In fact we purchased some chicks that were in a box with wire on both sides..this was not a tomatoe box but taller..maybe an oil box..it was a heavier cardboard that supported weight. This might be a little work for you but better that losing the birds..