Russell karting is your place to go.
That is the iame 5 degree taper on the TT75s.
Russle has different styles, 1-piece, and hubs that accept different tooth count drivers.
The later is easier, as there is no pulling required for a quicky tooth change.
Just remove the crank nut, & end washer, and the driver slides right off, new one slides on.
But too rich for my pocket book, so I just by the one-piece style.
http://www.hegar4.com/zc150/index.ph...8d6dd7862b466d Here is the link to hegar i think there cheaper than anywhere else. I would get the i piece driver with the changable driv er teeth. I think the super taper reedjet was $99 with your choice of teeth. Check it out foryourself.