Realize the other options but found Carastow wheels vary in price dramatically, scaring off many including myself. Looked on internet and can be as low as $173 each. plus freight from a tyre place in Geelong. Looked around and here in Adelaide are available for $183 each, in Cavan from a trailer parts mob. Hope this helps get your van under cavan. You will get your money back because they appear to be a quality item. There are many places to find out about trailer gear, all close by but near the fruit and veg markets is the distributor i am not allowed to mention. Send a message to ask if you wish.
Finally fitted the Manutec Carastow wheels available here in Adelaide, Cavan. I needed 2 and negotiated a very reasonable price each. Very good quality and actually a farm machinery product. Combined with the Trailer Mate, also helped the process. Only had to get another set of wheel nuts as the Carastow had slightly elongated stud holes and my nuts were chamfered and enclosed at the other end. If needed a cheaper ratchet jockey wheel would help but found it quite easy to push in on my own once the jockey wheel was realigned for the direction intended. Lowers the van heaps and I hopefully enough to relieve your problem.