Actually, the Mac's keys are derived from the Lisa, whose release well predates the Apple IIe (the first II with the apple keys). Except for the numeric keypad, the Lisa keyboard differed from the Mac only in that the Lisa used an Apple symbol whereas the Mac used ⌘.
I remembered that the Mac Plus (1986) had ⌘, and that the //e and //c both had Open/Closed Apple keys, but wasn't sure about the transition through Lisa and the original Mac.
Wikipedia has both the //e and the Lisa with a release date of January 1983. But of course the Lisa project goes way back!
