Can you clamp the workpiece to the cross-feed of the lathe and put the reamer in the chuck? I know that's kind of backward, and may take some fiddling to get it lined up with the headstock, but might be worth a try. You might have to machine something to get the work at the right height, but lining it up horizontally should be a piece of cake.
Or maybe stick some round stock in the opposite end for a center point and machine a piece that will slide on it that's supported by a steady rest?
[on edit] Sounds like Jerry got there first with nearly the same suggestion.
Last edited by klhansen; 05/04/2023 12:55 AM.