Unbelievably I have actually managed to fix mine. Eagle6 bits turned up in a couple of days despite being Christmas, so not bad. As mentioned earlier, the sector gear had broken a tooth, which had then stayed where it broke in the spur gear and caused the jam on the next cycle - which ended up blowing the fuse as well. Then I sheared off the rear power cables when trying to unscrew the stock pipe. Oh, and one of the bearings had shattered too.
Replaced bearings with Prometheus ones - I found using a gas valve tool to apply pressure worked quite well, no hammer required.
Replaced original