Exactly right! there are a whole lot of after-market part suppliers for major appliances like dishwashers, laundry washing machines etc. Some of them have a parts list and assembly schematic hidden in the machine.
Many washing machines are produced by the Whirlpool group under different brands, so it's not surprising that they would have a lot of parts in common and thus also feed a large aftermarket. Import brands like Samsung and LG tend to be much worse on parts availability and service information (and according to some statistics, also reliability.)