bolt in front stubs
Try speedwaymotors.com in Lincoln Neb.
I dont know of anyone that makes a bolt in version. These are complete assemblies and you weld them to your frame rails.
With your Chevy truck, you might be better off grafting in the front stub of a Nova or Camaro. These are bolted into those vehicles.
Another bolt in front stub is the Ford Aerostar Van.
You might want to compare wheel tracks and see what is closest to your truck in track width.
The Aerostar unit is a rack and pinion steering setup.