I think any header wrap you get from Jegs of Summit will do the trick. Racing headers routinely idle at 800 degrees and peak over 1900 so you should be OK. I know the roundy-round guys wrap their headers and they are sustaining well over 1500 degrees constant during a race and the wrapping lasts a whole season. Heatshield Products makes awesome stuff too. I was speaking to Steve Heye at Heatshield Product and their "Heatshield Armor" holds in the most heat and is the most durable.Mine is rusty also. High heat and cheap stainless is showing here also.
I am going to wrap mine. I believe that will allow for a passive partial regen.
Although I believe that will only save a bit of fuel. Not actually increases DPF longevity.
Does anyone know of a good wrap that will survive wet and very hot conditions?