The stuff i ended up getting was unbacked Johns-Manville R-30 insulation, 16 on center, 100% fiberglass. Had to buy 25 foot roll and only used 7 feet. Actually had to peel it in half to fit my application as it was 9" thick when unrolled. I checked the specs and it met a 1150F test for non flammability so i believe I'm good. Plugged a few entry points while i was in there. Im good with it, hope the wife can recover. Big thanks to @Blind Squirrel for the offer on the good stuff but I needed it ASAP. Putting money away now for a new oven. 'cept all the ones new are computer controlled and Ive read post on them lasting 2 years before a sensor goes bad. We've had this 15 years and I've only put one $12 Ebay ignitor in it.