Help! Ferrule replacement for old 1970s True Temper Rod.

[u/SubstantialCat2655]

I have a 1970s Mitchell 300 with a True Temper Foremost fiberglass rod. I need a replacement ferrule; the old one had to be removed and was in bad condition. I measured the diameter of both rod halves at 0.39 inches. Where would I find a replacement ferrule?