if you cannot find a used metal one...you might try a Fiberglass version , a repro that Ames sells FP 191L (is part no)...it is for 67,68...but may work with some 'rigging' on a 69...have not tried it myself..

I DO know the outer ends are a little different on 69 ,but 67-68 may still "work"..giving the airflow its designed for