A Jack Kirby story from Journey into Mystery 81 (June 1962). Looks like it signed "Kirby and Ayres" ( the inker ). No mention of Stan Lee. He wasn't always credited in the older comics, although he later tended to take credit for everything.
The dragon in this story has been compared to "Fing Fang Foom", who first appeared in STRANGE TALES #89. (Oct. 1961)