Wilson's to Leyendecker's (3 Rivers) would be my recommendation to start out.
Not that Hatchery to Wilson's is that technical. But I'd recommend getting feel for your boat and oars so you won't be embarrassed dropping out of the launch at the Hatchery. The thin, fast water there can turn you around pretty quick. Dropping down to the mouth of the Calawah is more bark than bite, but the chute out of the Ice Box might give you problems if you aren't comfortable with your boat. Not a good place to get sideways. The rest is a cake walk.
Have fun be safe and if in doubt wear a PFD.