Help Identifying Duster Rear End

be patient and they show up for decent prices from time to time
i bought my 8 3/4 for 300 about 3 years ago, but that was an open differential

if you're doing racing, i would go with a sure grip

or, if you are so inclined, get a ford 8.8 rear end, chop down the long axletube to fit a short axle and go with that
but, i think you are running small bolt pattern, so you would have to address that