Need sturdy brackets to replace many drawers

I don't know the manufacturer of the rails but have been using Richelieu plastic brackets that are too small and constantly break. I need at least a 1" slot to fit the rail. Mounted against the back. If you have them, I would like to get about 10 pairs. Please let me know if you have something to replace the brackets or do I need to replace the rails with brackets? In that case, I would like to get 5. Thank you.