@Thatwasherguy—No problem! Glad you found the actual date of manufacture by the nub! That was an inconsistent practice from around the mid-'60s until sometime in the '80s. You really got a GREAT deal for $11.99 and the low-mileage condition!
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All—I thought the same motor was used for the 200-Series & 2000-Series, and that the blender motors were introduced in 1974 with the 1400-Series (launched in 1973) when the top vents were added to the hoods and the Edge Kleeners to the bottom plate. Further, I understood that the later pancake motors coincided with side hood vents.