Really, any crumbly biscuit that turns "cakey" when wet would work.
Hmm... I will see what I can find. I might also need some
experimental subjects volunteer tasters to try the result on: I fear eating a whole ripple cake myself, appealing as it might be, would give me a cholesterol overload
Really I'm not sure why Arnotts haven't extended over there, I feel like Ripple biscuits and tim tams would be big hits in other countries.
They probably would, but we have our own well-established biscuit companies, selling broadly similar products to a pretty much saturated market. It's very difficult to break into a new market in a country thousands of miles away; even within the European Union, I don't think there's very much trade in things like biscuits across national borders.