To free it up you are going to have to take the wheel off. Remove the axle nut and washer. then use a plastic hammer or rubber mallet to punch the axle out of the wheel. Use a brass punch if you must use a punch. Using a steel hammer or steel punch will likely screw up the bolt threads.
Once the axle and spacers are out then you work to free the inner hub from the outer hub. Once free, you can get to the brake shoes and actuator shaft. I am sure the shaft is stuck in place. Use WD40 and the brass punch to remove it.
You are a braver man than most. The bike is 30 years old, abused and in need of hours upon hours of work. Parts are not going to be easy to find either.
Google " motorcycle salvage honda ". Also try " antique honda
motorcycle parts ". Check your library system for a service manual. Also try
www.repairmanuals.com . You must be related to "Scotty" of Star Treck fame. He could fix anything.
Best wishes on the project Scotty.
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