Stop in for a cup of coffee

Man there is a 63 413 for sale needs a bore kind of tempted but the rebuild would be $$$$$
if you went stock, sure. But IF the walls are thick enough, you could bore it to 426 where pistons are easier and cheaper to find. That said, get the block numbers off of it, it could be the performance block that was never turned into a max wedge. Those are high nickle content and worth a rebuild as they can go to 426 with ease