i dont know about other states but my state has a needle exchange it is 100% free plus they will deliver for free its to help with stoping aids from drug use
I think the cheapest way to get pins would be to borrow a used one from a junkie on the side of the street....He would probably let you use his for not more than a dollar...then you wouldn't have to pay all those shipping charges, etc. And if you ever needed more, I am sure that he would have more friends that would let you use their old needles, too.