The 2nd one you posted should be fine. Harbor Freight has a cheaper one, too. I would go with a WDH before a straight ball. Especially if driving a long distance. Your life and others on the road is well worth the $200.
http://www.harborfreight.com/10-000-lb-capacity-weight-distributing-hitch-system.htmlBut, if you go with a straight ball, get the ball as close to the van as possible, and use a riser hitch,
like this one which is 2 3/4 inches of rise OR
this one, which is a 4 inch rise. I wouldn't use that thing you're using. I don't think it is rated for heavy trailer towing.
This one, which looks exactly like yours, says that it is rated for 400lb tongue and 4000lb towing.