This Stan Lee vinyl figure is released by Funko in their POP! Marvel x Thor: Ragnarok vinyl figure series.
Funko POP! is a crossover vinyl figure series by Funko and other famous franchises such as Disney, Pixar, DC Comics, Marvel Comics, Simpsons, South Park, Uglydoll, etc. Each POP! figure is about ~3" to ~5" tall and crafted in a Japanese anime/manga super-deformed style (NOTE: due to the unique design of each character, the actual size of the figures may be smaller or bigger than stated).
The POP! Marvel x Thor: Ragnarok series features characters from the 2nd sequel to the Thor movie. In this installment, Thor is imprisoned on the other side of the universe, and finds himself fighting against his Avengers teammate, the Hulk, in order to save Asgard from Hela and the coming Ragnarök.