I personally have no opinion on that. I would comment though that the asking price for a wounded Hemi block seems to depend strongly on how bad the seller thinks the damage is. As to whether it is repairable, that is something that only a firm that welds cast iron can tell you. Years ago a shop in Williston, ND routinely welded cracks in diesel heads using a gas fired hotbox and cast iron rod. Perhaps you have access to that kind of firm, you'd just have to ask. As a note, I have a CH426 block that is windowed in two cylinders that I have been agonizing over for 20 years regarding which way to go. Sometimes it's not an easy decision. Good luck with your project.