If you have a port injection manifold the EZ-EFI system looks like this:
EZ-EFI system for port injection $825
4150 throttle body with TPS and IAC $540
Sensors (1 bar map, coolant temp, air temp) $60
Injector pricing depends on the HP level. The only restriction is that they must be high impedance. Can go up to 850 HP depending on the injectors.

If you use the bolt-on EZ-EFI with injectors in the throttle body (bolts on instead of the 4150 style carb), that's $1689. Good for 600 HP.

There are other variations (like 2 TB units) but these are the most common.