Watermelon Sour Schnapps is now available from Hiram Walker. Made with all natural flavors, the 30-proof watermelon schnapps mixes well with Absolut, AviÃ³n and Malibu, according to the company. It joins 39 other schnapps flavors that are available from Hiram Walker. The newest flavor has a suggested retail price of $9.99 for a 750-ml. bottle.