Hi Jim. Since the only original black seat pan for a 140 would have been for a Patio tractor, I really don't know what shade those were (I just haven't been around enough original ones to compare). All other 140's (and all 1968-1974 110, 112 & 120's that were "green") used a green seat pan. I've never had to repaint the 1975 and later seats as I have always bought the "generic" JD replacement seat TY15863 to put on my later tractors (and to use on my earlier tractors as a "user" seat, saving the original, smooth cushion seats just for showing). I guess I'm also old school and like the green color for those (as well as attachments like the integral and 3pt hitches) compared to the black.
Kent