273 Commando Valve Covers
Has anyone tried these for the plastic plug wire inserts? They look pretty close.
http://www.jimsautoparts.com/engine_ignition_parts.htm
"FW-395R -- SPARK PLUG WIRE RETAINER - 66-68 A, B & C Body Small Block 2 & 4 Barrel (holds two wires on top of the valve covers; snaps into metal tabs; natural nylon)"
And $5.95 apiece, not bad.
It looks like they have a part number of DI-301 shown for the other style pictured above in 65Val's Post #28 too ...
"VALVE COVER GROMMET - Used on 273, Big Block & Hemi engines (round, white plastic, insulates the ignition wires from valve covers or wire routing brackets)"
... but those are a whopping $2.95 each.