Chicken you might be able to find the brand Empire, in the NY area most regular supermarkets carry it so maybe they will carry it in your area especially since the plant is in PA.
Cheese also must be kosher, the biggest brand of kosher cheese is Millers, around here the regular supermarkets carry it, so maybe they will have it by you as well.
Hamburger will be tougher, its much harder to find kosher BEEF hamburger meat outside of a jewish butcher or supermarket (You might find Empire Chicken or Turkey burgers)
Salmon really isnt a problem and I wouldnt worry about that
Water , Seltzer, Coffee and half/half is probably ok as well. Flavored coffee might be a problem, but I wouldnt worry about it for now.