Your calorie counts are pretty good, Blast.

The native peoples often faced famine in the winter, even resorting to cannibalism in some areas.
That is a point worth mentioning.

Considering that almost all native tribes worked hard to store up enough food in the harvest seasons to last them through the hungry seasons, and if the aboriginals could have a bad harvesting season and end up facing starvation, then how good are the chances for somebody without their experience and knowledge of local foods?


Another thing to keep in mind is that all the really good food producing areas are heavily settled and under cultivation. They have been for a long time too.
The only exceptions to this might be a few isolated areas of coastline.This means that a person stranded today would likely face the prospect of foraging in areas that were always marginal at best.

They had better not be fussy eaters, and had better be prepared to do a lot of chewing to get those needed calories.

I am not saying it can not be done or that a person is doomed to starve in the wilderness, but it is not easy to hunt and gather enough in the off seasons to get by and you need more skills than most people are ready with.