The one on my pump has a dome on top top of the bolt.So a plain bolt will work?Sure. It's just a bolt with two locknuts. Might be a pain to get to, but doable.
Thanks, that helps me, tore a ligament in my wrist, so the idle screw is on hold for now.I know it has been longer than three days, sorry. In case you were waiting patiently, the stop bolt on the pump in my shop is a plain hex head bolt.