OK, all that's fair enough, if that's what you need then that's what you need.
a) I'm still worried about constantly running a solenoid like this.
b) They aren't fast enough anyway.
Also air is elastic, how long is the pipe/hose from the solenoid to the output? You could wind up not getting distinct pulses anyway.
The electronics and programming is easy and an Arduino can handle it, but you need someone with pneumatic experience I think.
Rob