I did replaced a broken gears, many time, and I have some original spare parts, the one you need, also, few of them. As someone said above is a press fit to the shaft easy to remove.
You dont need to remove the bigger gear, the one wit C-clip, just care about the smaller. Disassembler the whole gear block is a nightmare, dont' do it.
To repair the processor, back in the day, they should have a template to keep all the pieces straight.
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