So, I was going through my Box Of Ancient Controllers (AKA crap I've accumulated) and found one of these.  This pic isn't mine, I yoinked it from an Ebay auction, but it's the same stick.  It's an old analog PC joystick, built pretty well, but the key is the number of buttons.  It's a trigger stick (on the other side) and there is also a button near the bottom of the trigger side.  I haven't checked yet to see how many of these are wired in parallel.  Even so, it might be possible to attach this to an 8 way base of some sort...