Astro Vent Rubber ducts?

[judge1111]

Pulled these out of my early build (09A) 68 RS and was looking for replacement ducts since the rubber is dry-rotting. However, all I can find is plastic replacements...
They seem to be original with factory staples top and bottom but cannot find any reference to rubber ducts...anyone seen these before? Thanks!

[Sauron327]

I've never seen those boot types on the 68's I've worked on or parted out.