When you say plain hooks, are you referring to straight minnow hooks. If you are very few places to buy them. But I recently did a check and found that you can get the Red, Straight minnow Sickle hooks through Walmart. Not in store but you can order them online and have them shipped to store and no shipping. They also have the best pricing I have found on those hooks. If looking for Jig hooks to pour your own then that link Fatman posted is best place. If wanting to buy Jigs with sickle hooks, several guys on here make and sell them.
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Charlie Weaver USN/ENC 1965-1979