What month was your Bronco built in? Probably a pretty early '73 as most came with the J-shift type setup.
If a later model, then a PO put in a different shifter and/or case anyway, so it wouldn't be too far out of bounds to have shortened the shifter as well.
If it's indeed original, you've got a good combo.
Does it shift well? Can you get it into all positions without running into the end of travel of the plastic cover?
Paul