I am looking into purchasing a rectangular baking stone for making pizza and bread in my home oven. My oven is 16" x 22" and I'm looking for a stone that's close to those dimensions. I did a search online and came up with only one place that had larger than 14 x 16 (bakingstone.com) but they seemed a bit pricey. Does anyone know of a good source for oversized stones? Does anyone have any advice of what to look for in terms of thickness or material?