thx for the hint, been a LONG time since I,ve been there...Go to the Long Beach High Performance Swap meet.
https://www.toppingevents.com/ecology_meet.asp
I typically see used 67 and newer A body headers.
It is hit or miss on Mopar stuff. Sometimes, it is a gold mine of parts...other times, it is just a 4 hour walk.
Have fun!
OldMoparsRule!