For the push pin/clip fasteners, I looked in the fastener spreadsheet in the library, but did not turn them up. Perhaps Jim can double check me on that one.
I did not see any part number on the Osborn drawing. However, in the MPC illustration area for 66 Fairlane/Falcon they refer to a fastener part# 380457-S. That might not be correct for a 67 Mustang, but it is a starting point.