Hi,
Sunshine coast trailers do a good job on there products. If you can, get the most common sized tire avaliable. Nothing worse then getting to the tire shop and being told that the size tire you have is going to cost you twice as much as this one that is nearly the same but just different enough that it wont work with the ones on there.
Also, do a bit of research into the brake system you want on there. I don't know much about the differences and can't recommend one over the others but some on here may be able to.
Phill.