I picked up two identical wheel assemblies but am wondering if inflation can make a big difference on diameter. I picked the two closest at the store out of 5 available but the difference between the shortest and tallest appeared to be close to 3/4". The tires all seemed full but are rated for 50 PSI. I'm guessing the pressure was different and you couldn't tell the difference between 30 and 50 PSI without a tire gauge or load on the tires. https://www.princessauto.com/en/detail/18-50-x-8-50-8-trailer-tire-assembly/A-p8786030e
Who made them?
China
They're not duals, or on a driven axle, the height won't matter one bit. Get the pressure close though.
I haven't checked pressures yet but am thinking they are popped on the rims and filled without much regard for checking pressure. The taller ones did appear to have a more round profile and the shorter ones flatter.
Do yourself a favor and go have them foam filled, you’ll never need to worry about a flat or air pressure again…