8.25 "a"

Hello,
I am searching for an "A" body 8 1/4 rear. I went on the Hemmings web site to see what cars originally came with 8 1/4. Many models did thankfully, but i have not been able to source one from a local yard.I went on line and did a network search thru junkyard data bases, and have had some replies, but no Paydirt yet. I told them what car it will be going into, etc,.
Any ideas?
What should i pay for a limited slip?
Thanks russ