Automotive paint can be bought in spray cans at most auto parts stores, but if you are looking for something a better than you should find an automotive paints store. Sherwin Williams has them in most cities.
Go to Google and type in "where can I buy paint for chevy s-10 trim". You should find a link to autoanything. com. Once on the site Type what you are looking for in the search and you will find what you are looking for.