Vintage Pie or Stove Top or Camping Oven

I posted a similar oven a couple months ago. This one is a bit larger, pretty much a 12 inch cube, and it has a nifty gage.
Unfortunately I removed the rust on the top and it cam out mottled and streaked with rust remover residue. Now I need rust remover remover. I may just paint it dark brown.
Anyway this is open at the bottom as that is how it was heated. Could be placed on a stove top and used as an oven. Or even a campfire although that seems it would be difficult to regulate the heat. The gage would help with that.
Still thinking 1920s-1930s for this.