I finally got a new guide (also single-ring bolts). It's the same as the other one, except it's the high mount version.
The angle is off because the clamp is on the bend in the seat post. It can't go any lower, and any higher would make the angle worse. If they had something between the low clamp and high clamp, that would be perfect (as far as height anyway). It should do the job just fine though.
