It sounds like you guys are looking in all of the right places. In July you are usually pretty safe with regard to water levels in most areas. Just something to keep an eye on and try to get current info as the time nears.

As others have said, the big variable is what you want to fish for (timing). Most southcentral rivers get kings and sockeye. Plenty of rainbows (and people) in most as well. Another thing to remember, on most south central rivers, a lot of river miles separate the cool places to float and fish and the ocean. In other words, don't expect chromers. The last few years, most southcentral rivers have closed to king fishing early (prior to July 13) due to low returns.

Personally, for a king/sockeye combo, I would be looking at options out of Dillingham, Bethel, or King Salmon. Fresher fish and more of them. Lots of options.

On the flight, most folks charge $650 a flight hour for a Beaver. Do your homework on where to catch your bush flight from and you shouldn't have a problem staying under your $1700 limit assuming you have one load. Payload on a Beaver is usually around 1200lbs, which is plenty for 3+ gear. Cessna 206 is cheaper per hour, but can only carry 650 to 700lbs.