I popped into Photo Resource today and they do have FP4 and HP5 in 8x10. What is really amazing is the price, $86.00 per 25 sheet box (inc GST) which is exactly the same as I paid from Badger, but without the postage costs. 4x5 was the usual $45 per box, so no great savings there. So not only is there a local supplier I can buy from but they are cheaper than buying from the US as well!
Their stock on hand wasn't extensive, so if you wanted a lot of something it may pay to ring beforehand. I didn't see any Kodak or Fuji in 8x10 but they did have 4x5 from both brands, so presumably would be happy to order in anything you wanted. They appear to sell mainly to government & businesses but were very helpful to an obvious amateur like me.