How much more is it worth?

I'm not an expert in vehicle pricing, but I would think that if you could get the block repaired for $2000-$3000 you would get it back in the sale price. That is really only valid if you are going to do it to sell. If you plan on keeping the car and using it, I would put the block in the corner and send it along with the car if you ever do sell it and let then make the decision. I don't know if that block can be repaired and be a reliable driver.