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I think a Buck Gardner's double nasty will meet both your requirements of easy to use and financially prudent aka cheap.It's the best sounding one I have and it was $24. It's a double reed call.
DR-85 best poly double reed call. Good starter call until you want to invest in the high end calls. This call is made by Haydels and would be my beginner call of choice......easy to blow and they actually sound like a raspy hen....