A quick google search shows trailer weights around 4800lbs dry and 680lbs tongue weight. Actual delivered weights will likely be higher. Once it is loaded I think it will be too much for your van.
I'm assuming the van is a 1500 series? You need to consider the van weights before you decide. What is the vans' payload rating? Should be listed on the drivers door sticker. Subtract the weight of all the passengers and anything you may travel in the van with. What's left is available for the trailer tongue weight. Might not be enough.
Also consider that the tow rating (before the new standards) was calculated with only 150lbs for a driver in the vehicle. Any weight added to the van above that decreases the tow rating pound for pound.