Are the boat tubes PVC? I know some of the newer PROs can be purchased in hypalon neoprene and are likely to be grey on 420/500. If black and red it's likely to be Strongan Duotex, basically Zodiac's own PVC.
Anyway - get some pictures posted, easier to understand what you're dealing with and the repair procedure.
Any other information, age of boat, where it's kept are useful. You're in Oz, so extremes of temperature, maintenance routine and if it's covered or garaged all add to the mix.
Is that with or without VAT?