Thanks for the links and replies. The Hoffman box looks like what I'm looking for. Now if I can find one at a price that's a bit more affordable. The slide out cash drawers may not work for my set-up. I plan on using the box to mount on top of my roof rack. The basket has an upward lip along the edge. So, I'd have to accomdate room for when the drawer needs to be opened. Thanks for the suggestion!
Now to see if any areas around me on Craigslist is selling one of those Hoffman (or Milbank) boxes.
Thanks again!