Wheel requirements for my non-standard 2619 are 15x6", 6 bolts on 5.5". This is my wheel - they're cheap, look good, come with zero offset, and they're each rated for 2830 lbs:
http://www.ultrawheel.com/wheel/94/062-trailer/. I have no idea if your axle hub is the same. But for me, these particular wheels also create a safety advantage for the Dexter axle: The Dexter "grease cap" hubcap is held down tight within the "Ultra" hubcap. That prevents it from getting knocked of by a rock, allowing axle grease to spew all over (and possible freezing your bearings).