I'll just add another opinion here. If you EVER plan on running lower pressure for sand or loose ground, or deep snow, I would counsel staying with your stock 16" wheels and going with a high rated 285-75R16. There are a few out there that are 3750 lb. rated, up to 3950 lb. rate. I doubt you would have more than 7900 pounds on your rear axle. As was said, the stock wheels can take it, and they're probably 7" wide with a good back spacing to save your front wheel bearings; wide enough to run low pressure on sand. 19.5's have no seating ridge and are not recommend for low pressure running. They are great on pavement, however.
My fronts are 305-65R16's which are 33" in diameter, and still fit on my stock Dodge wheel.
I ordered the tires from National Tire with free shipping they were about $265 apiece. 3750 load rated; very aggressive mud tread, AND very quiet; can air down for sand; the best of both worlds. So, again if you are never going to be in sand, get the 19.5's and run the wheels off-em'.
It's a choice. This one is the least expensive.
regards, as always, jefe