'Girdered' moon ship model from an unmade movie?

Go to...

...and pay particular attention to Chesley Bonestell's truly dynamic painting of one of the moonships touching down [click third pix down].

Now, in "The Wrath of Kahn", when Checkov & the other guy are snooping around in the deserted shelter on sand-stormed 'Alpha Ceti 3' [I think], you'll see a partial model of the same girdered, tanked Bonestell moon ship: about a foot or so tall as a background prop.

That raises the question: what was it from? A movie never produced that would have used such ship models? It's sure not the old, vaguely similar, Lindberg moonship model kit...

I have no memory of such a distinctive girdered and tanked ship in any TV or movie then or before TWOK. "Conquest of Space" [George Pal] used the neat Von Braun winged Mars ship with jettisonable tanks and girders [from Bonestell's "Conquest of Mars" book] but that's the only one I can think of.

With the exception of Star Trek, Space 1999, C57-D, Disneys' Moon and Mars ships, 'Invasion of the Saucer Men' and a couple others, all other TV and movie spaceships from the 50s and 60s until "Space Odyssey" always used the classic 'cigar shape' fuselages with various fins & wings. I don't remember any foreign space films using the Bonestell design either.

Know anything about this partial ship model or the movie it came/almost came from?