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The V8 one will be the chev bolt pattern so they should be the same as the ones on the small blocks in the states. Maybe some import place brings them in for cheap?
I happened to be on the CRS websote today and noted that they do a converter "AP 52 Holden V6 T700 auto to Holden V8 & Chev "
So there you go, buy it once and get cheap gearboxes for a looooooooong time