Ford 9" in 1965 Barracuda...an option?
I'd keep looking for a sbp 8.75. Expensive; but boom; done. Little driveshaft work if you can't find an original. Otherwise an 8.8 from a 92 older Ranger; maybe shorten one side with a stock short side axle, but then there's wheels that don't match. and it's a ford part..But the drum brakes would work with your original brakes, just use an adapter to the metric lines or a double compression fitting..