Black&Decker GT360 hedge trimmer repairable?

[Slartybardfast]

My trimmer has been used a couple of times a year for twenty years. Recently it's taken to jamming on relatively small branches, but it works again when the branch has been removed. I opened it up expecting to find a stripped gear or drive belt but the electric motor shaft has a steel gear on it which meshes with a steel blade gear, an no signs of significant wear or broken teeth. My next thought was motor brushes but they're £12 a pair and even then it might not fix it. Before I replace it with a new one I wanted to make sure I'm not overlooking something, so any advice would be appreciated.