I wouldn't recommend that few of spokes for a person of your weight, unless they're strong deep v rims, but they could be fine. You shouldn't need any special spokes. 14/15/14 double butted will fine. You'd have to be more specific on the rim model for people here to tell you if you need washers or not.
As for hubs, just run a search for 28 on ebay under the rims and hubs category. Plenty of sellers will ship to Australia.