I know, it's expensive, but it's there for a reason.
It's rare to see a truck with one still there. Most have been thrown away, damaged from the last guy installing the wrong size battery or maybe a dingo took off with it. That block of wood/last years newspaper/old t-shirt isn't going to cut it.
No matter what happened to it, when it's not there bad things can happen. If yours is missing you've probably already noticed the corrosion from the battery. Or worse, rust is starting to rot away your precious under-hood battery stand. That part is welded to the inner fender and cannot be replaced by simply bolting in a new one.
Protect your precious Toyota metal and replace your battery tray.