I believe they did take special orders back then. I also read they would sometime have old stock and would put em together for example a 1967-68 neck could be put on a early 70s guitar or bass.
A factory stock neck would have both block markers and the binding in '67 or '68. These cosmetic upgrades occurred at the behest of CBS shortly after they acquired Fender in 1965. The binding came first in late '65, followed by the inlays the following year. It's possible that this instrument was a "bonus bass" -- so called because at the end of each production year, any unused parts from previous years would be gathered by the floor managers to be sent to the techs and assembled into sellable products. Thus, many anomalous guitars, basses, and amps have turned up over the years -- all of them perfectly legitimate. My brother has one such bass, a '67 Precision: no date on the neck heel, transistion 1965 headstock decal, pots and pickup dated to 1967, and "paddle-style" tuning machines. In the case of your Jazz Bass, I'd opine that the fretboard is extremely dark Brazilian rosewood.