get an sti. you always run the risk of fawking up the transmission. wrx tranmissions have ****ty shift forks and second gears. a sti trans upgrade will easily run you 4k dollars and your left with a ej20 engine. a ej257 has tons more low end torque and if you sell and buy a 05 sti you will have more power w/o having to do a bunch of bolt on mods. a simple tune and it can make 290whp on pump which is about a 50whp upgrade over the stock tune. good for lower classes in autox and will challenge 99% of the cars on the street. if your budget was 2k i might start mentioning go fast parts but with your budget your much better off selling the car and buying an sti. even if it means buyign a 1k dollar car to drive around whileyou shop for the right sti.