i payed ~150 but you might be able to find one off ebay cheaper
just carefully remove the oval trim around the bottom of the gear boot with a flat head screw driver and then pull the gear knob up off the stick.. might need some muscle though
and when you put the new one on just fix the gearknob to the boot with a cable tie and clip the oval trim in.. then put the gearknob on the stick and hit it with your palm as hard as you can till it wont move C=