I can see most of what I was hoping I would be able to see.
This is (the possibly shortened rear part of) a wrought-iron arquebus barrel of ca. 1520-40.
The small blade backsight is missing from the breech, and so is the pivoted swiveling pan cover of the ignition pan, as well as the forward section of the barrel with the second loop for a transversal stock pin; the rear loop on the underside of the barrel is still present. We may safely assume that the stock was originally fitted with a snap-tinderlock mechanism.
Attached please find links to my threads on three similar but perfectly preserved arquebuses of ca. 1525, 1540 and dated 1539, all in my collection:
Whether that iron 'rod' had any connection with that barrel I doubt very much; both rod ends do not make any sense at all for a loading process. It does not show any similarity to any actual ramrod I have ever seen.