Welcome to the Bunnings Workshop community. Thank you so much for joining us and sharing your question about hinges for your toolbox.
The store carries a few dedicated toolbox hinges. Would it be possible for you to post a photo of the hinge you have on your toolbox? This will give us a better idea of what it looks like and will let us give you a comprehensive recommendation on which hinge to use. However, if you're after a cover stay, I suggest a Goliath 185mm 100N Black Gas Strut or a Goliath Silver Metal Cover Stay. I've placed some links below for the toolbox hinges.