-1 isn't virgin, absence of a dash number is virgin. (no core plugs replaced)

413 HP engines were not always Max Wedges, some were also Chrysler 300 engines, Police engines, and Marine engines. The stamping looks pretty good (original) and there appears to be turquoise blue paint under the bright blue repaint. My guess is that (if the stamping is legit) it is a late 1962 or early 1963 Chrysler 300, Marine, or police engine.

I agree with Scott,the HP was found on all 4 barrel and dual 4 engines,car truck and marine.I have one in the shop that came from a Chrysler that had a 4 barrel carb.