The only source that I know of that may still have 3200 barrel hangers is Laibs Gunsmithing in Minnesota. They acquired most, if not all, the remaining 3200 parts from Remington a number of years ago. Their website is:
I bought a 3200 Trap brand new in 1976 and did not like the POI. I noticed by accident that the barrel hanger on a Skeet 3200 was not as thick and so I ordered one from the Remington factory and put it on myself. The result was just what I wanted, it raised the POI of the bottom barrel and did not disturb the top barrel. I'm sure Pat Laib will fix you up.