Although I keep looking into it I still don't own a 3D printer. My fix is to wrap a few turns of single stranded copper wire around the cracked section and glue that in place. Not as neat but usually does the job.
I originally did something along those lines, and while it lasted for some time, the shaft kept slipping and I had to open up the scope every once in a while to re-tighten the screws. Hopefully, no need to do that again

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Also, as the saying goes "To a man with a hammer, everything looks like a nail. This could have been hand made out of wood/plastic in less time than it took to print it.
Juan