I've never seen a NOS set of Hooker headers from this era, so this was a pretty exciting find for me. I have a nice set of '67-68 Z/28 Hooker headers and always assumed they were painted silver from the factory, based on what I could find after stripping off the white header paint, but this confirms it.
Can you imagine keeping such a killer set of headers in the box for almost 50 years???
Link to Vintage NOS Hooker Headers auction