I would imagine DVAP or Hidden Valley have those parts, but they will not come cheap. The few 73-77 A bodies I've seen and or bought parts from - in the El Paso TX U pulls - no buyers for the parts. A double edged sword with the Colonnade stuff - it's hard to find because little of it has been saved or squirreled away. You might try the third gen A body site:
www.g3gm.com. Good luck Dave S. dona Ana NM 88032