Well my local Pep boys actually asked me if I had 9" or 10" drums. So maybe there is actually a good part idiot at some places. If you want I can check with them and see if they can get the drums if you don't have any luck.
If you have a hand brake and the stock cables you should be able to fabricate a hook up to the 9" park brake set up. If you need the handle and cables I have one out of a 72 Demon. If you are interested email me.
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