The earliest confirmed date i can find on a 200 is June 17, 1968 (keybed date stamp of #49387). Yours has 1967 in pencil on the keyboard, which would be right, as they would use these boards on the next model after they assembled the keyboard.
Here is some more info for you:-
This series marks the single biggest change in the look of Wurlitzer's Electronic Pianos, which is retained throughout the rest of their run: Curved plastic tops, much lighter construction. But the action is a continuation of the last 140B series revisions, except that capstan screw is moved from far end of key to whip above key. Speakers mounted on body, not, as in non-hybrid models of later "A" series, in lid. (This is an easy way to ID.) The five 4th-octave rectangular reed screw plates are retained. Legs are now chrome, not wood.
There are now two speakers. On the earlier instruments, "The Speaker at the bass end accents the bass notes and the one at the treble end stresses the highs, to give a stereo effect." This seems to have been achieved through cone design. Date of switch to "same speakers" unknown.
Rarest 1st ones, 1968-early 1969, have legs with secondary supports, attached with slots/flanges instead of screws; faceplate labels atypically *below* knobs; different design to metal music stand ; grille patterns with gaps in middle (thanks Mark Cimarolli!).
