Heat shield
I have no familiarity with the Galley configuration of your 30, but my guess is there is something very wrong if things are getting scorched during the normal use of the oven. I installed an Origo two burner on my '83 Hunter 33 for it's simplicity. It has no oven, nor do we want one. Out boating is East coast during the summer. I don't need to generate even more heat down below. Besides, our feeling is, if we had an oven, and we did use it, and it got dirty, we'd have to sell the boat, cause we don't clean ovens!A piece of ceramic will transfer most of the heat through without being harmed itself. If all else is correct and a heat shield is required, the best way to make one up is to use a layer, about 1/4" to 3/8" of mineral insulating board topped with a sheet of metal. Stainless, alumunum, galvanized, won't make any difference. The insulator board looks a lot like what you think asbestos looks like. I can't remember what it's called, and for the life of me can't remember where to get it. How's that for helpful?My wife's advice? Cold-cuts, hamburgers, and the baked goods aisle of the local market.