Considering how far you are planning to travel, you should definitely use a good guide. Regulations and hot spots are ever changing. You will get the most fish per day this way vs heading out on your own. Being newly addicted to fishing myself, I have learned that I can easily waste a day looking for fish that are 2 miles away, upstream or downstream of where I chose to flogg the rocks.
At that time of the year consider a guide that will offer different locations/techniques as different salmon species will be at different areas within the river system at the same time.
If money is more of an issue than the time spent and you have access to your own gear ... you could always convince some of the old salts on this board to take you fishing. After all, there would be no reason to keep secrets from you since you live so far away. This method may only cost you beer and gas (and then some more beer).
Cheers,
Alex
... "high water" is when you can fish from your car.