actually,
there were several, the Green and gold was first for the Anniversary edition. the they switched to blue and clean white (brain if you remember i have that one), and the only change ive seen besides the color is the green had the old style bag clamp system, and the blue was updated for the screw on bag system. and there was one more, another blue with a round handle, and the two speed switch in the front of the handle, and a chrome hood. as opposed to the white painted hood, that was the last of the 260. i think Eureka ran the 260 from 57, to around even early 1960.