Welcome. Depending on the condition and mileage of your car, some of that money will be put to good use on general maintenance items (spark plugs, filter, tires, etc). In regards to the exhaust, loud does not equal high performance and there is a difference between loud and good. If you want to be as loud as possible, then you can get an off road mid pipe and muffler deletes but it will probably sound like ass and drone like crazy. You can also just go with open headers for free and be both the neighborhood ass and a moving cop magnet. I would personally look online or at local shows to see what sound you like. The 3V can sound real nice with the right exhaust. Websites like American Muscle usually have exhaust clips that you can use to compare different systems. As far as performance, the usual first mods are tune and gears. Long tube headers will probably be a good buy if you want to mod your complete exhaust system since they will give you some sound and small performance benefits. Just make sure you get a midpipe that will work with them. Beyond that, I suggest looking at suspension and tires. Power means nothing if you can't put it to the ground. Plan out what you want to do because $2500 will evaporate quickly.
I will say that exhaust is very subjective. The "best" sound can vary from person to person so just search until you find something you like. Those cars have been around long enough that someone is bound to have the sound you are looking for.