Eibach Sportlines aren't too bad. They lower about 2" but the ride is too soft for me. $200

Suspension Techniques makes a nice spring set. It lowers the car around 1.75" and from what I hear gives the best ride out of all the springs. $215

If you can find RSR Race springs (not sure if they make them for the 200sx) they have the highest spring rates you can find. I think they lower about 1.75". $215

They will all ride on stock shocks, but I recommend you get shocks that will match the spring rate for whatever set you go with.

Personally I would hold off and get a nice coilover set, so you can adjust the height and "stiffness", but I understand your on a budget.

Hopefully that helped and like josht34237 said, check ebay, you can usually find some good buys