There are four important parts in your circuit for current consumption calculation:
1. resistor dividers, a constant current as their outputs are loaded by CMOS inputs, no current
2. CMOS logic gates : they take more or less current according to individual logic states: check specifications and all states
3. Indicators with LEDs, take ~10 mA per LED and CMOS gate current in open or closed state
4. Buzzer driver, possibly the highest current of all. Current depends on pulse duty cycle.
My estimation with a 9V battery for the complete circuit is ~ 8-10 mA minimum, 24-30 mA maximum.
Make the circuit on a breadboard and measure the current in operation. Let me know how much I erred.