If the prize you won was called a Maple Bench and looked like this:
Then I think the box you're looking for was a clone of the RS mystery box of the same name - the team
has been swapping boxes and back and forth recently so it's my best guess. When the team does a swap like this, the items remain the same so the info
should be accurate. I missed this box release entirely so don't hold me to any specifics, lol.
If this is what you're looking for, you can find the full details and images for that box
here on the RS Forum.