PICS help identify this chunk section posi or not and value of it

So a buddy brings me over a center section for my 8 3/4
he says i have a 355 posi sitting in a bag all greased down ill sell you for your car.
I say well what posi is it theirs 3 kinds he cant answer that and i ask its a 355 not a 323 right he says yea 355. I then say case numbers please he says 489 case i say sweet

So it gets here gear says 323 and i count the teeth its a 323 and its not a posi that i can see maybe a limited slip or sure grip i think is what mopar calls it.

so i say you know this isint half of what you said it was he was shocked
and i told him not worth what your asking he says make me a offer
so what is this thing worth only good i think is that its a 489 case


chubs