actually 1964 is about right
because the style was changed to the 4 way hydrosweep on the 15 series and they came out in 1964. the previous machines, 14, 12, 11, 10 models all looked basically like this. i have (3) 12 models and a 14 and an 11 and the tubs all look the same to me!
the kdp-2 was the top load version on these kitchenaids. i picked up a kdp-2 summer before last in buffalo and just plugged it in last week for the first time. runs great, no leaks. gonna do a post on it soon i think.