How to people buy parts for classic cars that are no longer in production?

A challenge to owning a classic car is buying replacement parts when original components fail. There are a few options, some specialty supply houses create reproduction parts, but depending on the popularity of the car the availability is mixed, it can take some time for a custom part to be fabricated and it can be a costly option.  If the failed part is on hand, you can take the part to a local supply house, and compare the specs to modern parts in the parts catalog, and select the closest matching part. This is a good option for items like fuel filters and brake pads that have similar dimensions and functionality of the original part. In some cases, it may be easier to upgrade a component, such as removing a generator and replacing it with an alternator to upgrade the reliability of the classic car.