Where to find a 9 inch differential

[1243mjp]

I am looking to upgrade my 10 bolt in my 69 camaro as I just put in a 6 speed and I don't think the 10 bolt will live much longer and I am not a big fan of the current 3.42 ratio because I can hardly use the 6th gear. I like the 9in because of easier gear changes with the removable center section. What cars should I look for at the junk yard that have a good 9in differential in them. Also will I really be saving much money finding a junk yard axle and building I up or just ordering a mail order axle built with what I want.