Here are your choices for Hamilton. These carriers have GSM networks which are compatible with your Nokia phone:
I really can't tell which one is best since I don't have service with any of these companies nor am I from Hamilton. What I can suggest is that you ask around and see which of these carriers have good coverage in your area. You might also want to read carrier reviews here in the Cell Phones Etc. website as people sometimes post useful information there, which I hope would be helpful for you in making your choice.
To read carrier reviews, go to the carrier page and click on the Reviews tab. Each carrier from the list I provided are already linked to their respective carrier pages. I hope you make a good decision. Good luck!