Injectors are 450.00 and are for sale on the site.
With adding the CAI you will not be able to keep the stock airbox, that is why we offer the kit to work with the stock air box. Adding the CAI will put you around 265HP.
We do offer a basic reflash good for about +18HP and +20TQ.
The main reason why you want to add injectors is to allow the car to not run lean and ultimately run safer. The boost in HP in TQ is just a bonus.

Anthony