OP, your shopping list does not fit any 1/2 ton truck, once you add supplies and passengers. Truthfully, 24 or 25 feet is the about the max you will be able to pull with a 1/2 ton truck comfortably.
When the RV manufacturers "determine" that a trailer is 1/2 ton towable, they will use a base weight truck to maximize the trucks capability and then use a trailers dry weight.
The 1/2 ton truck will reach its GVWR or rear axle GAWR long before it reaches its GCWR.
On a trailer, the dry weight is a useless number. The dry weight will not include any accessory listed in the brochure as an option. This will include items such as the air conditioner, microwave, awning, TV, battery, full propane tanks, etc. Then you add your supplies. A trailer may weigh 500 to 1000# over the brochure dry weight when delivered with options.
On the truck, the tow ratings are based on a base model truck with only a 150# driver, and often, less than a full tank of fuel and no hitch (150#).
So you need to start by weighing your truck loaded for a trip with passengers and work with the information you have on YOUR truck.
If you truly want to meet your shopping list, you will need to start with a 3/4 ton truck.
Ken