Getting it weighed yourself is extremely easy. Either go to a truck stop and use a truck scale or to a place that has a scale (bulk agriculture supply, dumps, etc). 2 quick weighings and you'll know the exact weight of your camper. If you use a weight-distributing hitch (WDH), you may want to add a third weighing.
1) Truck and camper hitched up with WDH like normal
2) Truck and camper without the WDH (just tongue on the ball)
3) Park the camper somewhere and weigh just the truck
Keep all passengers, cargo, and fuel levels the same. Try to do all 3 weighings at once if you can.