Check out the J-Stik by Ultimarc. It's a modified Sanwa JLW joystick which is switchable from 4way to 8way from underneath, like Epyx stated. However, Ultimarc modifies the plate underneath so that it's easier to turn. They use nylon washers, custom springs and screws so that restrictor plate turns easier. I made the mistake of purchasing a standard JLW and it was near impossible to turn with the default hardware. But Andy at Ultimarc helped me out (great customer service as always) and sold me the components needed for the mod. But I should have gone to him in the first place. He also sells the longer shaft if you have a 3/4" wood panel. The Sanwa JLW is designed for metal panels so the default shaft is shorter by design. I'm not sure what you're panel is made of, but I'm assuming it's wood.
Good Luck!
DeLuSioNaL29