If you are asking for a small quantity of the larger syringes, like 5cc or so most pharmacies will sell to you as the IV drug users generally use the small insulin syringes that only measure up to 1cc. They definitely should sell them to you if you tell them that you dont even need the needle, just the syringe body to accurately measure something.
If you get desperate and cant find any, let me know and I'll get you some from my pharmacy...you'll have to drive up here to get them though :(