I-Pac 4, USB w/ CD, lightly used, $50 + shipping
Street Fighter 15th Anniversary Joystick, $50 + shipping
The I-Pac was used for a while inside the joystick.  I cut the wires to the joystick to do it.  The joystick still has the wiring harness, you'd just have to re-mount the joystick and rewire the harness to use it in its original capacity for Xbox/PS2.  Or put the I-Pac back in it.  Pics below.