I know this isn't exactly the throttle pulley, but here is a picture of the throttle cable support bracket I fabbed up. I ended up bending it down a little, but it supports the throttle cable, and gives a smoother "pull".
It's simple to make, you just weld a strip of steel on to your existing throttle cable bracket. It has to be bent to the appropriate radius.
The grooves are to locate and retain a couple of heavy tie-wraps to hold things in place.
The original idea is from John Taphorn.
Rocky