Are there any stampings on them that can be looked up?
That is how I identified the headers on my truck and their intended usage as well as junkyard and swap meet headers.
On the head flange there will be numbers stamped into it, or possibly a tag on the tube with part numbers.
Junkyard headers for my 1995 Suburban were $80 for a $215 set.
The tag on the tube has the manufacturer and part number listed...
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$50 Swap meet headers from my kids '55 Bel Air that are $327 from Summit now.
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Easy to look up numbers.
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