Hmmm this one harder to explain basically the genuine article which is demonetised, was a 8 real and had it's center punched out to make a Holey dollar and a dump. However due to their rarity there are restrikes, including Perth Mint
have made both silver proof restrikes and nickle copper proof usually in sets. Either the Holey sets or a commerative fakes of all the famous and rare coinage of Australian. Sort of like the Maria Thersa thaler which get restriked but for circulation in those time (more for numismatic purpose).
However due to fact that not many people know this they just lump it in junk coins so it very likely some sort of copy.
There is also a one dollar copy of it :) which I happen to noodle.