[spacepenguine]

If all you are looking to do is relay values from joysticks to the motors with the smallest investment is probably an arduino. All you need is the board and a long USB cabel to tether to it from a computer with joystick connected. <http://principialabs.com/arduino-python-4-axis-servo-control/> is a good starting point for setting this up (victors and jags take servo pwm signals).

The arduino uses its own script language, but it's pretty simple to lean and the ide is free with plentiful documentation.