You may consider using a basic 12v linear actuator. They will never achieve a speed of >1m/s, but then, thats fast for pneumatics. Motorized actuators essentially use a leadscrew powered by a motor which suits the load and speed needs.
Any of
these actuators should suit your needs. I filtered the search to show high-speed actuators.
Also, they also present the cost benefit. These will probably never hit $200.
To control their position, you will need a sensor kit. I believe
http://automationdirect.com sells them, don't remember the price. As to speed control, basic PWM will do the trick.