Especially If you have a stick, I recommend wider, stickier rear tires, as without that, you won't have much traction in first gear. More so once you start getting more power from your engine.
Couldn't give you a good price idea though, I build my own stuff. But either way, you'll enjoy the new gears.
Edit: Figure out what speedo gear you need and buy it from a Ford dealership. Its real cheap. Also, you'll want to change the fluid in the rear end after a (IIRC) 300-500 mile break in period. Grab yourself a bottle of friction modifier for the fluid change while you are at the dealership for the speedo gear. Lastly, don't wear nice clothes while changing the rear end fluid, gear lube REEKS, and it will never EVER come out of clothing. As a matter of fact it will probably take a few days to wash the smell from your hands.