10'' rear brake drums

Where could I find a pair of these for my 65 Barracuda. I thought I saw these really cheap in the new Classic Industry dream book
After putting on my glasses I see they are available wB-bodies and have a wider width. A local parts store told me I could use the ones from a duster, the difference was they look a little different on the back side. It has a flange that is supposed to help keep water out
I purchased one and they will fit, but are rubbing against the back plate.