Well having been born in 1984, I was a bit of a late starter in terms of Joes.
I didn't get just one first Joe, I got a whole bunch (a few incomplete) secondhand from my cousin, all at once, some time in '88.
Sci-Fi (complete, rifle holder on backpack broken)
Tomax and Xamot (complete)
Crimson Guard (with backpack only)
Barbecue (Backpack and axe only)
Frostbite (no rifle, but Snow Job's ski gear)
Mainframe (backpack and computer only)
If you mean something I got myself, brand new, that has to wait till 1993, and even then it's a bit iffy which one it was. I know I got two Joes that year, so it was either Vega from the Street Fighter line or Ace and the Ghoststriker X-16.