I've received several requests for an explanation of why I don't think this pipe is repairable in the accepted sense of the word. Meaning 1) undetectably, or if detectable, in a way that's aesthetically pleasing; 2) at reasonable cost; and 3) is durable enough to last for the life of the pipe (or close to it).
In this case,
-- The shank is a shell and will continue to crack and leak along the de-facto score line that's the rustication
-- Repair bands aren't available in that diameter, meaning one would have to be cut from a piece of sterling silver tubing
-- Such cut rings aren't flexible enough to be heat-shrunk in place, meaning the already-too-thin shank wall would have to be stepped/inletted to receive it
ll in all, it COULD be done, but would be labor-insane, ridiculously expensive, and highly unlikely to last long in use because the eggshell shank wouldn't be stable.