You can also buy washing machine parts from a bricks and mortar store - if you can find one nearby. You will often have to end up ordering it at the store and then going back to collect it when it finally arrives, as many stores do not keep any but the most common parts now. They do this to reduce their own costs as it is no point them carrying a lot of parts that may well not be needed. They could sit on the shelf for years until that model appliance went out of date and then they would never get sold.
To make it easier for you, best to know the specific make and model of your machine. The model number and the serial number help locate a compatible item for your property. Prices vary according to product quality. Do not be fooled by brand names though. Being expensive does not necessarily denote quality. Choose what is tried and tested by other consumers.