If it only has 1000 miles on it, I would drive it as is.
My 216 in my 46 half ton has a Jasper Rebuild Tag, unknown mileage and runs just fine in today's traffic around town. Your big truck has low gears, as long as you don't want to constantly drive over 55 mph, you'll be fine. It should have plenty of low end power, just don't be in a hurry.
Once that engine wears out, they you can replace it with a 235 or retrofit something to it.
