I don't think public libraries carry any Marx or Mao, nor physical bookstores. That's why left-wing parties usually set up shop as, literally, a shop, for books and periodicals that are not freely available due to "market forces."

Mail order has been prone to interference/surveillance by the USPS at various times. The worst was the decades in the antebellum South of course, which censored abolitionist literature.
Happily for the purity of American morals, Ayn Rand is pretty much always available. Often, like 1984, she's pushed as a "classic" in sections devoted to improving YA minds. (For much the same reasons.) The rape scene in The Fountainhead I'm sure has been very educational to less sophisticated teens for years now.
Now I hate to be hoity-toity, but...The Jungle? Sinclair observed he aimed for America's heart and hit its stomach. Being where the national soul resides, The Jungle is a YA classic too. (It is well known the concerned adults, teachers and librarians who make up the YA classic reading lists do insist on certain works aimed at improving the morals.) The Jungle makes a case for government banning poisonous foods being sold for profit. This kind of socialism is innocuous enough yet allows the listmakers to congratulate themselves on their daring.
No, I think what you need to read as a genuine counterpoise to Rand's utopian thriller is Jack London's dystopian thriller, The Iron Heel. After reading the chapter on the Chicago Commune you could follow up by reading Heinlein's The Moon is a Harsh Mistress, especially the sequence describing the peacekeeper assault on Luna City.