Cocaine hydrochloride IS cocaine, the fine white powder drug. It is distinct from free base cocaine, commonly known as 'crack', which is made by stripping the hydrochloride ion using a strong alkali. Crack is popular because the free base form is more pharmacologically active, meaning you get more bang for the same price, or alternatively, the same bang for a lower price.
I don't know if CVS or Walgreens would have a reason to stock in at the local store, but they could likely get it from their regular distribution. Yes, a medical doctor can prescribe this but it takes considerable extra paperwork (and receives DEA scrutiny). It would likely be more common in a hospital setting, usually as one ingredient in a compound.
