My favorite holiday cookie recipe -Starlight Mint Surprises

My mom still makes these for Christmas. She says it is getting harder,however, to find the mint/chocolate wafers that the recipe calls for. Got any ideas where to find them? Starlight Mint Surprise

Sift together 3 cups of four, 1 tsp. soda, 1/2 tsp. salt. In a separate bowl, cream together 1 cup of butter (could use 1/2 cup butter and 1/2 cup shortening or margarine. Add 1 cup white sugar, 1/2 cup brown sugar and blend together. Then blend in 2 eggs; 2 Tbls. water and 1 tsp. vanilla. Add this to the dry ingredients and mix thoroughly. Chill the dough. After chilled, take about one tablespoon of dough, and encase a chocolate mint wafer inside the dough. Form into a ball and place on a greased sheet. Press a walnut half into the top of the ball. Bake at 375 degrees for about 10-12 minutes. Recipe makes about 4 1/2 dozen.