Ophorus or Bordeaux Wine Trails will both offer options. Fair warning, they tend to visit the same wineries, so just pick one if you go that route.
Bordeaux can easily be done without a guide. Saint-Emilion is easily accessible by train, Pessac Leognan is easily accessible by bike, and there are two wineries within the city of Bordeaux which can be visited. I always recommend people take a look at Sauvistication (https://sauvistication.com/planning-chateaux-visits/). It will teach you how to navigate on your own.
Safe Travels!