BladeTech Revolution straight drop belt holster. About $25. Don't forget a real gun belt, like the Wilderness Tactical Original Instructor in 5 stitch, and 2 mag pouches (that's all you can wear for IDPA) and with left over $$$$, get some Peltor Tac 6 electric ears.
https://shop.blade-tech.com/product_...1#.WdD8zGiPKM8