There is a Lake about 15 minutes by a fast skiff from Sitka that has chrome bright Sockeyes holding in the estuary by the last few days of June, it is called Redoubt Lake and the river is a waterfall right into the Saltchuck. If you find a way to get there be sure and have serious bug dope with you the no see-um's are worse at that place than any other I have ever encountered!!!
There is a Fly Shop in Sitka that is run by a friend of mine and he will be able to give you a good low down on what is happening from the beaches and the road system. ( I think he calls it "The Fly Away fly shop" Bill Mcnally is his name great source of current local info.
If you are going to try and fish Kings in the Salt with your Charter boat connection be sure and take your own rod and such with you. With very few exceptions there will be no fly equipment on the boat.
The kings from Sitka that time of year are great fish have a good trip.