Mitterteich Silver and Porcelain Coffee Set

Q: My demitasse coffee set consists of a pot, 6 cups and saucers, a sugar, and a creamer. The pieces have a white porcelain interior and a sterling silver exterior. The pot is 6 1/2 inches tall and has a raffia wrapped handle. The bottoms of the coffeepot, sugar, and creamer are silver and are marked “Sterling Silver on Porcelain” and “Foreign.” The cups and saucers are porcelain covered with a thin layer of silver and are marked with what looks like a flower over the letter “M” and “Bavaria.” The words “Arboix, Colon, Sterling-Silver” are written in green script underneath the mark. A note on old adhesive tape on the bottom of the pot says “Purchased in Panama 1933.” There is some light wear to pieces where a person would hold them. Can you give me some information and valuation?