There were a variety of sides for these trailers, at least 2 patterns shown below. The one marked "Rozelle" sat in a junk yard in inner Sydney for a couple of years, but I don't know what became of it.
The trailer (and Inter) you have pictured to a Sydney club member. Another the Sydney Club member had one of these trailers with mesh sides that doubled as a loading ramp. Very handy. He did have it for sale a while ago but I don't know where it went. Perhaps you do, Diana??
One of these trailers had troubles at Corowa one year and had to seek the services of a local engineering business in Corowa to fabricate a new wheel to enable the trailer to get back home to Sydney, but perhaps you knew that, too?
You say the wheel is the same as an International Tractor? I had thought the wheel looked similar to a LR 101FC.