That's a very cool find, thanks for sharing the pics. The obvious 'stashed his gear, never to return' backstory, makes the real-life man and events behind the cache all the more intriguing.
I'd have guessed 1930's, based on the art deco style of the graphics and writing on those coffee cans. The depression years were a time when many jobless men sought out the old gold rush era locations, with dreams of making their fortunes. Most were lucky if they even managed to scratch out a meagre living, given their only resources were basic hand tools and sweated labor. If those cooking utensils could talk, I'm pretty sure they'd tell a story of hard times and cold, hungry nights beside a smoky campfire.