Jeff I' m not to far from you (Jackson, TN here). I am not particularly familiar with the pawn shops in Dyersburg but if you dont know what to look for when dealing with used firearms or dont have someone to take with you who does, buying a used gun isnt a good idea. (You are underaged anyway and would have to have an adult purchase the gun for you in the first place.) You will probably spend $300+ on just about any used bolt actions from companies like Rem, Win, Ruger etc... And at that price range they will probably have " average" scopes atop them like Tasco, Simmons etc... If you get enough money saved up by the beginning of next year you could possibly buy a brand new Remington 700 ADL (my brother owns the Buck & Bass Sports Centre' s in Memphis and Jackson and I believe they sell them for under $400) But then you wouldnt have a scope for that price. But you could start " small" and get a Tasco 3x9x40 Pronghorn mounted and bore sighted for well under an extra $100. Or you could buy the 710/Bushnell package rifle (or the Savage pkg rifle as well) also. While none of the optics are the best, they would allow you to " learn the basics" and should last you long enough to when you get older and start working regularly, then you could save up for better optics.
Thats why I would recommend the ADL. In either a ' 06 or 7mag you would have a rifle that will kill 90% of the worlds game under a majority of conditions in a rifle that will last you a lifetime. Plus it is accurate enough to merit placing better optics on it in the future.

Good luck and if I can help let me know: [email protected]
RA