Due to rising sugar prices (thanks to lobbying by the American sugar industry to restrict foreign competition), in the late seventies virtually all soda bottlers and candy makers went to fructose as a source for their sweetener. As a result the taste in all the products that transferred from sugar to fructose suffered including Coke. The switch from glass to plastic also hurt. Plastic and fructose. That's why Coke doesn't taste as good as it once did.
Woodmans grocery store in La Crosse, WI carries Coke in glass bottled in Mexico and made with sugar. It tastes just like Coke did 40 years ago. 12oz for $1.29, but worth it, especially since we drink perhaps one a month, each.
I first tasted it right after having my teeth cleaned and could _feel_ the sugar, so it will remain an infrequent, special treat.
Probably available anywhere they carry a good selection of ethnic foods.