Is there a reason you are looking for a Tums equivalent instead of Tums? Like vtw said, it's sold here. I've been buying Tums from a few different Farmacities here for a few years.
A word of caution on Acid Reflux, what burns is the esophagus, when you ingest a Calcium Carbonate tablet it goes right Thru, to protect the stomach, a thick liquid like Pepto Bismol or similar coats the esophagus, where the burning is....!!IMO