The worth of a lbp SG 8.25 w/ 3.91?

I have a large bolt pattern 8.25 rear end in my Duster, sure grip with 3.91 gearing. Its a strong rear but I believe my small block is surpassing it's beef. Anyone have a decent estimate at what this is worth? Complete drum to drum.
I,d say$3-400 depending on condition(rusty or freshly painted)My 2 cents.