I would say that would be enough to cause a problem! you may have got away with it though. clean it all properly, regrease the gears, straighten the grease plate and 'peen' it back in place. a soldering iron should be able to melt wee bits of the plastic surround over so it holds the plate in place securely.
I (being an optimist) would bet that cures the problem.
Plenty of meat on those brushes IMO.
Seems like a plan. I am wondering whether the bearings are OK? Looks like a bit of excess armature end float going on.