A real Detroit will have nothing resembling regular spider gears. A factory Trac-Loc style diff will; however I don't believe the 60 and 80 series to be interchangable. Looks like a D70 or D80 Trac-Loc loaded carrier.
Also, if he's selling it without the pinion gear, it's essentially worthless. The ring & pinion are lapped as a matched set and you can't re-use a pinion with a different ring gear.
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