WNC Potter seeks 12x24 shelves for wood fire kiln

From Dian Magie:

I'm looking for some 12x24 shelves for my wood fire kiln. Checked with Larkin and they want $75 for "slightly warped" shelves. Would like shelves without slits. Any ideas other than Minnesota?

Have an idea? Email Dian at dian.magie@gmail.com or leave a comment here.