"If I'm right, I'm going to try and convince my husband to get a better truck. Any suggestions as to an affordable truck that can pull a 5th wheel of this size? We don't mind buying used."
Most husband won't need convincing to get a bigger truck.....
However, if you choose the right time to travel (cool, light wind, no snow), a route with as few large grades as possible, pay attention while driving and stay at 55 - 60 MPH, use good braking techniques when going downhill you'll do OK with the 1/2 ton.
