Preserved fruits and vegetables are extremely cheap and available in the US. Food in general of any type is actually very cheap in the US unless you live in NYC or downtown SF. These prices are for average chain grocers, HEB, Krogers, Wegmans, etc. Not bulk shops like Sam's or Costco. Some grocers also tend to focus on lower costs and will be cheaper than this such as Fiesta.

Frozen typically runs between $1 and $2 a lb depending on what you want. Some cheaper mixes can be had around $0.50/lb.

Canned typically comes in between $0.25 and $1.00 a can depending on brand. The chain grocer near me also routinely has sales on canned vegetables for $0.15/can if you buy 20 or more. A can is typically about 15 ounces. It can make up the bulk of a meal for 1 person, or serve as a side for about 3.

Dried bulk products such as rice or pinto beans are also reasonably cheap though more expensive now than they used to be. Beans run about $0.25 to $0.50/lb depending on how much you buy at once and rice is about half of that.

Fresh produce varies a lot by time of year and location but can typically be had for under $1/lb if you aren't choosey. Double to triple for anything labeled organic.

Meats start around $1 to $2/lb for chicken thighs and pork shoulder and goes up to about $20/lb for premium beef cuts.

I routinely make stuffed bellpeppers (bell pepper, rice, hamburger, tomato, and spices) for lunch and then end cost comes out to around $1.50/lb.