Oh the horror! The horror! I now have visions of masses of unique youth in places like Portland and Seattle lost in a daze, jonesing for their fix. And leagions of baristas wander the countryside like the 100 ronin, without purpose causing havoc.
On a serious note,
Tea can be made from any number of herbs and plants. Coffee can be made from substituites such as chickory, burnt grain, or roasted acorns and even dandelion roots dried and roasted.
And you mention the Gulf Coasts don't forget that Coffee is produced in the Caribean and Mexico too. So, it should be available in and around the East Coast, Gulf Coast, Southern Border.
As I think about this, the Gateway to the Spanish Main module, the ship patrols the area in the Caribean and West Africa, again a good trade route where one could put in a cargo of coffee and rum and sugar from the Caribean, and even Tea from Africa and I would imagine some manufactured goods from the US.
Also, with the hop around Central and S. America you could probably pick up some food stuffs as well.
And lets not forget durring the California Goldrush and even the lumber rush in the 19th century many ships would sail up and down the West Coast of the US to Panama in about a week. So, a couple sailing ships working up and down the West Coast hitting Mexico and other portions of Central America they could easily pick up coffee from such places and bring them back to the west coast cities, and again rum would be available as well
Now, that also leads me to think that within a year or two after things fall apart and fuel being unavailable old clipper type ships will be refitted and pressed into service as well as larger pleasure sailboats and most likely a new cottage industry of newly made wooden schooner and clipper type sailing craft craft for coastal trade.
So, fear not Web, coffee will be available.