d60 rears are in the 3/4t 67-72 chevys, and just about every 3/4t-1t ford and dodge truck, are very wery common.
why are you even looking at reverse rotation gears? that is jeep and ford only high pinion axles, triple the work to put in a chevy and triple the cost.
since you are in the n/e you should talk to this guy,
www.extremeaxlesales.com
$650 for that axle is retarded beyond all belief. if you cant find an axle i could pull and ship you a 14bff with your choice of gear for less than $650.