Can Anyone Identify This Intake

I got this intake from a guy along with a bunch of other car stuff from a neighbor who was cleaning out his shed. It's a dual plane intake and looks like a small port (273-318) piece. There are no identifying characteristics like the Pentastar, firing order, cylinder numbers or other tidbits of information I'm used to seeing on Chrysler intakes. It is cast iron not aluminum and VERY heavy. Can anyone tell me what size engine it fits or possibly how old it is, is it 60's or 70's? Thanks.