Bummer. Well, you need to get that rod out. Do you have enough rod sticking out to get a bite on it w/ vise grips? If so, do that and start twisting it out or beat it out (hitting on the clamp) while holding the vise grips carefully w/ other hand. Upper in vise and hopefully in a receiver block. . . if not then use lumber and your imagination.
Then if you can't find pencil rod, go browse Lowe's and HD for something long and sturdy to punch the round out. Maybe 3/16 all-thread and grind down the threads a bit?
Then go to your local shop and take that ammo, with out seeing it it's hard to tell. . .