Aussie models related to overseas models
Leon will probably be able to give a much more knowledgeable answer than me for this specific case (Wilkins Servis connection to Maytag) but this sort of thing is very common here, and not just with washers but throughout manufacturing industry.
Australia is a small population in a huge country, in the 1970s we were about 15 million give or take, now 24 million. Our land mass is about the same size as the continental United States. It has simply made economic sense to pay a license fee to locally manufacture an overseas engineered product, rather than start from scratch and re-invent the wheel for a tiny market. Just about all our washing machines were made here either by an overseas owned company (GE, Hoover) or an Aussie company licensing an overseas design (Email made Westinghouse, Malleys made Whirlpool.) I don't know about Simpson, their Fluid Drive was based on a Beam design I vaguely recall, or maybe Speed Queen? Their later models were unique to Australia but the transmissions looked a bit Maytag to me. (Agitator and shaft looked very Maytag.)
Some companies did a bit of both, for example Hoover Australia made Hoovermatic twinnies pretty much the same as the UK ones, but kept an older model in production after it was updated in the UK; their full size top loaders were to a Blackstone design but got "Australianized" over successive model updates; Hoover front loaders were originally slope front Keymatics made almost identical to the Welsh equivalent, later Hoover front loaders were at first imported from the UK to a revised Aussie specification (3236H), this model was later manufactured in Australia with substantial modifications, including stainless steel inner and (later) outer drums, no heaters in base models, no dispenser drawers, different timers and much shorter cycles. (the Zodiac series.) Their mid-size top loaders were based on popular Japanese models, changed to incorporate existing generic Aussie parts.
Wilkins Servis was similar, they made wringer washers and twin tubs to a UK design, when large top load autos became popular they did a deal to use Maytag technology rather than have to engineer a new model from scratch, at huge cost for a tiny market. (They didn't have anything equivalent in their UK model range.) These models that used technology they licensed from overseas companies were often badged as "International Series." They also sold a small Japanese washer, like the tiny GE that was sold in the USA for a while, it was another of the International series. I had one, they screwed everything in knots just like the GE ones do. The Wilkins Servis one was sourced from Toshiba from memory. (I had one and spare parts came in Toshiba packaging.)