Can someone please date this A833?

Alaskan hit the nail on the head. It has the dual shifter location for B and E body. So the story jives that it's from a 71 Runner. Hemi cars and the 6 pack/6 barrel cars had the 18 spline input as standard equipment. The 4 barrel 440 engines came with 23 spline, 18 optional. Regardless of this info, it still won't work in your A-body without some heavy mods for shifter location. If it's dirt cheap, just snag the dang thing and flip it or use it for trading stock.