Hi guys. I know this post is a bit like our cars and getting on a bit, but I have just had both rear wheels off my 25-25 to clean the diff oil off my brakes etc, I also failed my warrant of fitness due to a front wheel bearing.
I tried a few bearing suppliers and one tracked two assemblies down from Australia! (NOS)
I have just installed them in one wheel only. They cost me NZ$550 so not cheap but pretty lucky to find these!