Australian Knitting Mills, or Australian Woollen Mills.. not really sure what name they go by.
It's run mostly by a bitter old knitting machine technican / wizard with poor social and marketing skills, and his partner.
Last time I knew anything was from ~2021 visiting their factory in Coburg to buy some socks and long underwear, at which point they were already looking at moving/retiring to the east coast.
Bob told me they were the original manufacturer of Explorers, before his business partner wanted to take things in a different direction, whereupon they split the business and we can see Australian Woollen mills kept striving for high quality but didn't evolve with the fashions while Holeproof set fashion trends and sent machines overseas but gradually enshittified.
The pair of "Ultra thick hiking socks" are my most frequently worn socks and are still going strong since 2021: https://www.aust-woollenmills.com/shop/hiking-sock-ultra-thick-100-merino/hiking
No online ordering, just phone and bank transfer. If you're gonna make a massive order I'd call them to confirm when someone will actually be there, at either their Coburg (8 Trade Place) or Collingwood (13 Hood Street) places. There's a few phone numbers scattered around their website.