I plan on using a corny as a secondary for some specific reasons. For now, it'll be just that, a secondary. In the future I might force carb some beers.
I see that rebuilt ones are cheap and plentiful. They mention seals, pop-off valves pressure valves, dip tube and a bunch of other stuff. What exactly do I need to buy to make a rebuilt corny into a beertight chamber that I can fit an airlock onto?