well post the photos !
chances are its a 8mm x 1.25 pitch J bolt
it can be larger if supporting a coolant bottle too ?
i have seen many SHOP made Varietees of this also 🤔
but the OEM one is distinct and the truck will have 2 / dual batteries also
are you from a NON-USA Far Away Location ?
what engine is in this mystery toyota vehical ?
i was looking through my assortment of coolant jug brackets and actually found that has a battery J bolt as part of it ?