Mouser and Digikey are the largest distributors of electronics components for prototyping/low volume production. They have a decent filtering system that helps you pick the right part for your application.
Digikey has cheaper shipping costs so we will likely use it for most of our purchases unless a component is out of stock
Some CubeSat specific components may need to be sourced elsewhere i.e. cubesatshop
To source a part, getting comfortable with the filters on Digikey and Mouser is a must. The following criteria are the team’s standard when selecting any part: