Re: What are your 5 must fish rivers in Colorado in early July?
Here are a few campsites I have noted in passing:
1. Swan Mountain Road near Frisco along the perimeter of Dillon Reservoir (USFS White River Nat'l Forest).
2. Hwy 9 approximately 5-10 miles north of Silverthorne (along the Blue, also White River Nat'l Forest).
3. Hwy 82 east of Aspen about halfway between Aspen and Independence Pass (on the Roaring Fork).
A good campground information resource for much of the area you mentioned is USFS map for the White River National Forest.
Another good campground information resource is the Colorado State Wildlife Recreation Area listing. Many are situated near good fishing and a few allow camping.
I fish much of the area you mentioned fairly frequently but have always stayed in Breckenridge so I have no first hand knowledge of campgrounds, only observations as I blew past on the highway headed for a stream. The campground I mentioned on Hwy 9 north of Silverthorne is literally on the Blue River in a nice fishing stretch betweed Dillon Reservoir and Green Mountain Reservoir. I believe the campground along Hwy 82 and the Roaring Fork is across the highway from the river but my memory is a bit vague on that point. The Roaring Fork in that area is smaller and faster water, plunge & pool for the most part, with mostly smaller fish but still fun and very beautiful.