mine broke a month ago -- i was in the same quagmire you are in. mine was still under warranty so i wasted my time and had it replaced with the original glass slider. i had the same thoughts you had - why replace the POS because it will only break again.
-local glass shops did not know of any replacement latches, they only wanted to replace the entire rear window or the slider for bigger bucks than if i had dodge do it ($117 for the part - excluding labor).
-you could go with an aftermarket electric one, but that is pricey -
-your solution of angled aluminum sounds like the best answer - i took a loop of wire and molded/tightened it to slide over the latch - pOdunk, but it worked.
ron