This is an early 302 4 barrel intake, unique to Mustang.  With such an early casting date (July 1967) it was likely going to a GT350 Shelby.  

302 Ford 4 Barrel Cast Iron Intake Manifold 

Fits all 260 289 and 302 engines 

1963 1964 1965 1966 1967 1968 1969 1970 1971 1972 1973

This is a used FoMoCo cast iron 4 barrel intake manifold.

No problems

The shipping cost is US48 and ebay global only but I can quote other places as needed.