[Russ/40]

Of the responses, I'm mostly leaning toward soldering the crack, as whatever is done will be done by me. What soldering techniques are you suggesting? Brazing, Silver soldering or? The crack does leak when the block is filled with water. You can see the crack as a rust line. Will solder wick into the crack when rusted?
Might try stitching, as the area is so accessable.