You're going to want at least 14 inches, preferably 18 inch diameter.

Are you 100% sure you have an edible pineapple variety? (they do often sell the ornamental variety that, while more hardy, isn't very good for eating)

I picked my first pineapple that I grew from a store bought fruit this year, it lived the last 2 years in a 5 gallon pot and seemed happy.

I have about the same wait time for pups as I do with cutoff tops, about 2 years.

There is a gal across the canal from my last house that had hundreds of pineapple plants in 3 gallon pots all around the house. If they can't go wide they should go deeper.

Water them and do not let them die of thirst.

These are fun to grow I have a few at different stages. The bigger ones are in 3 gallon and can fruit in those no problem.

Yes they are the edible type. I had a pineapple the first year it was about 2/3 the size of a store bought one but had good flavor. The pots are relatively deep and I do water often through the top of the plant, I can't see roots protruding out the bottom yet. I apply fertilizer the same say. During the winter I didn't need to keep them watered as often and I do notice a little brown on some leaves but since the weather broke they seem to be taken off, Their newer leaves are a little purple which I am suspecting P deficiency, I haven't fertilized them all winter and probably will hit them with a quick batch of self made fertilizer.