Use any light dried (DME) or liquid (LME) from any manufacturer. All are pretty good these days. Light = Light, Extra-light, Pale, Pilsner, Golden, or anything similar.
I don't know what your recipe calls for, but you can substitute one for the other. 1 lb LME = 1.25 lbs DME.
Sorghum is a different grain than the standard barley malt, and will give a very different taste.