I second what abrightwell said, Having a narrower trailer with the wheels under the camper will raise the height significantly. You would be looking at a galley height of 42″ with 12″ wheels. A typical kitchen counter height is 36″. A narrower wheel base would also raise the center of gravity and be less stable (not unsafe, just not as stable as a 5′ wide).
If you haven’t already, take a look at the finished campers here http://teardropforum.com/forums/topic/completed-clc-teardrop-camper-photo-gallery/ It looks like almost half use 4′ wide trailers and many of those with smaller wheels. Just something to consider.
I ended up with the CLC Trailex trailer myself after numerous issues sourcing either a HF or NorthernTool trailer. However if you want a wider trailer with a lower price point then i’d recommend the Ironton 5ft. x 8ft.