"Post Brine" for Lacto-Fermented Cucumbers (Dill Pickles)
Yes, you can use the brine you pickled them in. Covered plastic leftover containers are actually very good for storing pickles - you don't have to struggle to stuff them in jars. You can throw away the dill weed and garlic and other flavorings, just keep the pickles and enough strained brine to keep them submerged.

Keep in mind, of course, that such pickles are not preserved, so they must be stored in the fridge, and should be eaten within a short amount of time - one or two weeks at most.