"Is there an octagonal gate for the Hori Hayabusa?"
A common question, currently there is no octagonal restrictor gate/plate for this joystick. However, unofficial modifications do exist. These mods remove the official square plate and instead inserts a Sanwa GT-Y octagonal gate or GT-8F square gate with a GT-Y insert.
SRK member therobin sized the drilled screw hole at 1/8". You can purchase pan-head screws easily at any hardware store. The screws' lengths would require a few more millimeters in size than the existing screws that came with the Hayabusa, to properly attach the modified plate to the joystick.
You can find details here:
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