Don't know how much of the seller's story is real... the D-40C was a standard model for a couple of years in the mid-70s, and this one doesn't say "special" or "custom" on the label. The only thing I see that is out of the ordinary is the lack of a pickguard, and that could have been "lost" during a re-finish (don't kow if the electronics are special or not).
It also appears to have a JLD bridge doctor in it (based on the "string-thru" brass pins), and the strings don't look to have much break angle over the bridge.
Still might be a sweet sounding mahogany guitar!