You are talking about a rear end that is 35+ years old and unless the truck has never been driven from day one you have to go by what the condition is today.

On Wednesday a friend and I pulled a 8 3/4 housing with axles, brakes & drums, but no 3rd member at the local Pick-n-Pull and it was $150.00. This was out of a '56 Belvedere that had been treated to a 383 four speed transplant back in the day

Everything we got was very useable, the 10" drums still had chamfer, the brake shoes looked new and the hardware was new, the u-bolts were not rusty and will be re-used. The housing had been converted from keyed to flanged axles and they were good with recent Timken bearings, so you know it was not OEM. So as I see it, we got several hundred dollars of value for $150.00

And since this is going into a '55 Belvedere street rod, it all bolts up.

That is the real way to determine value