I’d like to see a Marti report or some sort of documentation before I believe any “one of one” statement, but a GT 351 Ranchero, like this 1972 GT 351 for sale on Hemmings.com, does indeed seem like a rare bird. Is it $30,000 rare, though? From the seller’s description:
1972 Ford Ranchero GT 351, factory 4-speed, 1 of 1 made, numbers matching car, frame-up restoration.
See more Fords for sale on Hemmings.com.