Buy any Case pocket knife that you like. Made in Pennsylvania, USA since about 1890 or so. The carbon steel blades sharpen faster than any knife I ever used, altho you need to keep them oiled against rust.
If USA made is not a concern, the French Opinel is an awesome knife that works well and is dirt cheap ( about $15 ) The carbon steel is best for edge retention and ease of sharpening.
Both knives are available with stainless blades for less maintenance. The stainless blades are top notch too, and are 95 percent as good as carbon steel. Stainless is the best choice for most folks for a knockaround knife.