dwh,
Thank you for finding it. Do you happen to have any experience with it?
Not that one, but decades ago I had one of the military surplus units (US issue, Viet Nam era) that the OZTrail is modeled on, and I'd seen the OZTrail on the net before. My old .mil model worked great, but you had to pre-heat the water before pouring it into the bucket and it weighed a ton. 3 gallons of cold and 1 gallon of boiling was my usual recipe. I'd just throw a rope over a tree, lift it off the ground for filling it and then and haul it up to working height after it was filled.
And that nipple looks like it's probably just standard 1/2". Shouldn't be a big deal to replace with a brass nipple unless it's some weird Aussie metric thread or some such.