I don't see that it's been suggested before, so I'm going to copy this from another thread where I posted this same thing, but if you are in the market for new tires and wheels anyway, I'd recommend upgrading to 19.5" wheels, and run 225/70(~32" tall) 14/16 ply tires. I run them on my 1 ton pickup. The wheels have a 4500lb load rating, and most 225 tires have about a 4000lb load rating. If you have room for 245's they are around 5k. They also last much longer than a 10ply 16" tire.
Diesel power magazine did an article on them a while back.
http://www.dieselpowermag.com/tech/1104dp_100000_mile_semi_tires_for_dualies/
Here is their review a year later.
http://www.dieselpowermag.com/tech/1205dp_19_5_inch_vision_tires_and_wheels_one_year_later/
I run the Vision 81 wheels, and Hercules H902 tires.
http://simpletire.com/hercules-225-70r19.5-59217-tires?utm_source=Google&utm_medium=cse&utm_term=18690&gclid=CO76m-PA0bwCFSzNOgodvS8A_A
My package of 4 wheels/tires mounted and balanced was about the same price as a set of good 16-18" wheels and decent tires.
Edited: I just saw the last pic, and your trailer is 6 lug, all the 19.5's are 8 lug. Don't think that's going to work for you. Sorry about that.
