Cracked Exhaust Manifold Again, Headers This Time?

[delaware39]

While adding the phenolic spacer between the carburetor and manifold, I noticed a crack in the exhaust manifold between cylinders 5 and 6. When I bought the car in fall 2015, it had a cracked manifold between 1 & 2. It took me months to find a replacement, and now it's cracked, too. I'm considering buying new cast iron headers from Langdon. I don't really care about improving the performance, I just think another used manifold would crack again. The pictures show them installed on somebody's engine (definitely not mine!) and a picture from Langdon's website. The extra money for ceramic coating is supposed to help keep the engine compartment cooler. It does get mighty hot in there. It also gets really hot around the pedals in the cabin.

Any thoughts and/or opinions, including any experience with ceramic coating?  I'll be posting this on the POC Facebook, too

http://www.langdonsstovebolt.com/store/#!/Plymouth-Dodge-Cast-Exhaust-Headers/p/1396124/category=18665943