Neoporteria bicolor or Eriosyce islayensis
(This plant comes in a 3.5" pot. You will receive a very similar plant to the one in the picture. It may or may not be blooming at the time of your purchase. The plant is shipped in its pot to prevent any damage to the roots).
Originally from Northern Chile, it grows in very dry desert areas . It is a small cactus with very woolly areoles and dark spreading spines. It is indeed very variable and has received many names.
Flowers: Diurnal, wide funnel form, yellow 1,5-2,5 cm long
Propagation: Usually propagated from seeds
Some of the information in this description has been found at desert-tropicals.com, llifle.com and cactus-art.biz
