I got it from someone who made it actually, in his shop, and he just happened to have some extra. The carbon holds up well, and does a good job of holding the steam in. Due to how it rests on the top it is also very stable.
Roger, I did indeed try to spot weld first with some scraps, and it just seemed to blast right though both layers of Ti with just a single spark.
I will probably try it again soon.
Overall I am very pleased with the boil times, but what makes me more happy is the trail weight of this. I can grab this kit and a few solid fuel tabs that will last 3 days and be at about 5 ounces max.