There are a handful of independents in the US like
http://www.pleasanthillgrain.com/can...anned_beef.asp
and
http://www.foodservicedirect.com/ind...pared_Beef.htm
who actually can meats, or resell them, but you won't find those products in the supermarkets, you'll have to mail order them directly. I've heard some folks say they like the product but then again...some folks also like spam.
Who knows.
In the US you will more readily find MRE's from military/camping suppliers; various freeze dried meals from camping stores; and of course a good hard salami or other "shelf stable" product from any good "german deli". A couple of companies sell similar products (often nowhere near the quality, certainly no cheaper) in supermarkets.
As a nation, we're not big on "tinned beef". And if you see the Underwood brand tinned meat spreads...they're easy to find, but if you don't like Spam, you probably won't like them either.
Our version of shelf-stable protein is peanut butter and jelly.