Excellent to know. I'm going to use the diffuser for an 11-inch diameter All-Clad pan and a 12-inch diameter Le Creuset pot. I posted the link to a 10-inch diffuser, but have since found a 12-inch one, which is what I'll get. There's a metal fabricator near me that I will contact to see if they'll be able to help. I think the larger width or diameter is the way to go with these big pots. Here are the online links to the 12-inch plates should you be interested:
https://www.ebay.com/itm/335502106579
https://www.ebay.com/itm/335502106574
You could also contact Stryker Welding in Stryker, OH if you don't want to go through eBay: https://strykerweldingandfabrication.com/stove-top-heat-diffusers/ The phone number to order from is at the link, 419-682-2301