The second supplier lists it as a John Deere part, and people had referred to it as for agricultural equipment. Just assumed tractors and other field equipment. Hadn't thought about it being used for stationary equipment, but that makes sense. Water pump, generator, etc.
The first supplier just lists it as a truck part. I'm not sure if they are two different casting suppliers, or if they are just selling the same part. Used to be available through The-Co.com real cheap, but they don't seem to carry it anymore and the eBay prices have been steadily rising closer to the cost of a pair of Langdon cast headers. Cheaper of the two is $202.98 compared to $307 for the Langdon exhaust with heat plate. Unless you can find an original HD 292 exhaust, those are the two cheapest options.
http://www.langdonsstovebolt.com/store/#!/Stovebolt-Cast-Exhaust-Headers-for-GM194-230-250-292-engines/p/1395980/category=18665955
