help please, please!

Where can I get the right hand (passenger) side "connection for warm air
fan" (as Bentley names it on p 26.4 (pic 26-333)) for an '81 vanagon
(westie)?  It's the piece that goes between the fan and the heat exchanger,
and ours has never been there so we've never had heat. The piece we need is
unlabeled in the pic, only the left one is labeled.

Please help save our trips -- my wife refuses to wear a sleeping bag as a
passenger any more. We need warm air. I've hunted the wreckers' yards, no
luck so far.

thanks
Al